diff --git a/services/core/java/com/android/server/wm/AppWindowToken.java b/services/core/java/com/android/server/wm/AppWindowToken.java
index d46b535386437..a3f7ac6d6c0d4 100644
--- a/services/core/java/com/android/server/wm/AppWindowToken.java
+++ b/services/core/java/com/android/server/wm/AppWindowToken.java
@@ -676,6 +676,34 @@ class AppWindowToken extends WindowToken implements WindowManagerService.AppFree
         mPendingRelaunchCount = 0;
     }
 
+    /**
+     * Returns true if the new child window we are adding to this token is considered greater than
+     * the existing child window in this token in terms of z-order.
+     */
+    @Override
+    protected boolean isFirstChildWindowGreaterThanSecond(WindowState newWindow,
+            WindowState existingWindow) {
+        final int type1 = newWindow.mAttrs.type;
+        final int type2 = existingWindow.mAttrs.type;
+
+        // Base application windows should be z-ordered BELOW all other windows in the app token.
+        if (type1 == TYPE_BASE_APPLICATION && type2 != TYPE_BASE_APPLICATION) {
+            return false;
+        } else if (type1 != TYPE_BASE_APPLICATION && type2 == TYPE_BASE_APPLICATION) {
+            return true;
+        }
+
+        // Starting windows should be z-ordered ABOVE all other windows in the app token.
+        if (type1 == TYPE_APPLICATION_STARTING && type2 != TYPE_APPLICATION_STARTING) {
+            return true;
+        } else if (type1 != TYPE_APPLICATION_STARTING && type2 == TYPE_APPLICATION_STARTING) {
+            return false;
+        }
+
+        // Otherwise the new window is greater than the existing window.
+        return true;
+    }
+
     @Override
     void addWindow(WindowState w) {
         super.addWindow(w);
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 7cd99714c00cb..0b39d65c9407b 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -1085,12 +1085,13 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
         return null;
     }
 
-    int addAppWindowToWindowList(final WindowState win) {
+    void addAppWindowToWindowList(final WindowState win) {
         final IWindow client = win.mClient;
 
         WindowList tokenWindowList = getTokenWindowsOnDisplay(win.mToken);
         if (!tokenWindowList.isEmpty()) {
-            return addAppWindowExisting(win, tokenWindowList);
+            addAppWindowExisting(win, tokenWindowList);
+            return;
         }
 
         // No windows from this token on this display
@@ -1128,7 +1129,7 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
                 }
             }
             addWindowToListBefore(win, pos);
-            return 0;
+            return;
         }
 
         // Continue looking down until we find the first token that has windows on this display.
@@ -1154,7 +1155,7 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
                 }
             }
             addWindowToListAfter(win, pos);
-            return 0;
+            return;
         }
 
         // Just search for the start of this layer.
@@ -1175,7 +1176,6 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
                 + mWindows.size());
         mWindows.add(i + 1, win);
         mService.mWindowsChanged = true;
-        return 0;
     }
 
     /** Adds this non-app window to the window list. */
@@ -1778,23 +1778,20 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
         return mLayoutNeeded;
     }
 
-    private int addAppWindowExisting(WindowState win, WindowList tokenWindowList) {
+    private void addAppWindowExisting(WindowState win, WindowList tokenWindowList) {
 
-        int tokenWindowsPos;
         // If this application has existing windows, we simply place the new window on top of
         // them... but keep the starting window on top.
         if (win.mAttrs.type == TYPE_BASE_APPLICATION) {
             // Base windows go behind everything else.
             final WindowState lowestWindow = tokenWindowList.get(0);
             addWindowToListBefore(win, lowestWindow);
-            tokenWindowsPos = win.mToken.getWindowIndex(lowestWindow);
         } else {
             final AppWindowToken atoken = win.mAppToken;
             final int windowListPos = tokenWindowList.size();
             final WindowState lastWindow = tokenWindowList.get(windowListPos - 1);
             if (atoken != null && lastWindow == atoken.startingWindow) {
                 addWindowToListBefore(win, lastWindow);
-                tokenWindowsPos = win.mToken.getWindowIndex(lastWindow);
             } else {
                 int newIdx = findIdxBasedOnAppTokens(win);
                 // There is a window above this one associated with the same apptoken note that the
@@ -1804,16 +1801,9 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
                         "not Base app: Adding window " + win + " at " + (newIdx + 1) + " of "
                                 + mWindows.size());
                 mWindows.add(newIdx + 1, win);
-                if (newIdx < 0) {
-                    // No window from token found on win's display.
-                    tokenWindowsPos = 0;
-                } else {
-                    tokenWindowsPos = win.mToken.getWindowIndex(mWindows.get(newIdx)) + 1;
-                }
                 mService.mWindowsChanged = true;
             }
         }
-        return tokenWindowsPos;
     }
 
     /** Places the first input window after the second input window in the window list. */
diff --git a/services/core/java/com/android/server/wm/WindowToken.java b/services/core/java/com/android/server/wm/WindowToken.java
index afcdc41321409..38225cc4421e5 100644
--- a/services/core/java/com/android/server/wm/WindowToken.java
+++ b/services/core/java/com/android/server/wm/WindowToken.java
@@ -24,6 +24,7 @@ import android.util.Slog;
 import android.view.DisplayInfo;
 
 import java.io.PrintWriter;
+import java.util.Comparator;
 
 import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
 import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_KEYGUARD;
@@ -82,6 +83,26 @@ class WindowToken extends WindowContainer<WindowState> {
     // The display this token is on.
     private DisplayContent mDisplayContent;
 
+    /**
+     * Compares two child window of this token and returns -1 if the first is lesser than the
+     * second in terms of z-order and 1 otherwise.
+     */
+    private final Comparator<WindowState> mWindowComparator =
+            (WindowState newWindow, WindowState existingWindow) -> {
+        final WindowToken token = WindowToken.this;
+        if (newWindow.mToken != token) {
+            throw new IllegalArgumentException("newWindow=" + newWindow
+                    + " is not a child of token=" + token);
+        }
+
+        if (existingWindow.mToken != token) {
+            throw new IllegalArgumentException("existingWindow=" + existingWindow
+                    + " is not a child of token=" + token);
+        }
+
+        return isFirstChildWindowGreaterThanSecond(newWindow, existingWindow) ? 1 : -1;
+    };
+
     WindowToken(WindowManagerService service, IBinder _token, int type, boolean _explicit,
             DisplayContent dc) {
         mService = service;
@@ -168,19 +189,31 @@ class WindowToken extends WindowContainer<WindowState> {
         return -1;
     }
 
+    /**
+     * Returns true if the new window is considered greater than the existing window in terms of
+     * z-order.
+     */
+    protected boolean isFirstChildWindowGreaterThanSecond(WindowState newWindow,
+            WindowState existingWindow) {
+        // By default the first window isn't greater than the second to preserve existing logic of
+        // how new windows are added to the token
+        return false;
+    }
+
     void addWindow(final WindowState win) {
-        if (DEBUG_FOCUS) Slog.d(TAG_WM, "addWindow: win=" + win + " Callers=" + Debug.getCallers(5));
+        if (DEBUG_FOCUS) Slog.d(TAG_WM,
+                "addWindow: win=" + win + " Callers=" + Debug.getCallers(5));
 
         if (!win.isChildWindow()) {
-            int tokenWindowsPos = 0;
             if (asAppWindowToken() != null) {
-                tokenWindowsPos = mDisplayContent.addAppWindowToWindowList(win);
+                mDisplayContent.addAppWindowToWindowList(win);
             } else {
                 mDisplayContent.addNonAppWindowToWindowList(win);
             }
+
             if (!mChildren.contains(win)) {
                 if (DEBUG_ADD_REMOVE) Slog.v(TAG_WM, "Adding " + win + " to " + this);
-                addChild(win, tokenWindowsPos);
+                addChild(win, mWindowComparator);
             }
         } else {
             mDisplayContent.addChildWindowToWindowList(win);
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
index 74e8c9d52836e..d933cb377ef08 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
@@ -29,17 +29,19 @@ import android.view.IWindow;
 import android.view.WindowManager;
 
 import static android.view.WindowManager.LayoutParams.FIRST_SUB_WINDOW;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_STARTING;
 import static android.view.WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
 
 /**
  * Tests for the {@link WindowState} class.
  *
- * Build: mmma -j32 frameworks/base/services/tests/servicestests
- * Install: adb install -r out/target/product/$TARGET_PRODUCT/data/app/FrameworksServicesTests/FrameworksServicesTests.apk
- * Run: adb shell am instrument -w -e class com.android.server.wm.AppWindowTokenTests com.android.frameworks.servicestests/android.support.test.runner.AndroidJUnitRunner
+ * Build/Install/Run:
+ *  bit FrameworksServicesTests:com.android.server.wm.AppWindowTokenTests
  */
 @SmallTest
 @Presubmit
@@ -55,6 +57,36 @@ public class AppWindowTokenTests {
         sWm = TestWindowManagerPolicy.getWindowManagerService(context);
     }
 
+    @Test
+    public void testAddWindow_Order() throws Exception {
+        final TestAppWindowToken token = new TestAppWindowToken();
+
+        assertEquals(0, token.getWindowsCount());
+
+        final WindowState win1 = createWindow(null, TYPE_APPLICATION, token);
+        final WindowState startingWin = createWindow(null, TYPE_APPLICATION_STARTING, token);
+        final WindowState baseWin = createWindow(null, TYPE_BASE_APPLICATION, token);
+        final WindowState win4 = createWindow(null, TYPE_APPLICATION, token);
+
+        token.addWindow(win1);
+        token.addWindow(startingWin);
+        token.addWindow(baseWin);
+        token.addWindow(win4);
+
+        // Should not contain the windows that were added above.
+        assertEquals(4, token.getWindowsCount());
+        assertTrue(token.hasWindow(win1));
+        assertTrue(token.hasWindow(startingWin));
+        assertTrue(token.hasWindow(baseWin));
+        assertTrue(token.hasWindow(win4));
+
+        // The starting window should be on-top of all other windows.
+        assertEquals(startingWin, token.getLastChild());
+
+        // The base application window should be below all other windows.
+        assertEquals(baseWin, token.getFirstChild());
+    }
+
     @Test
     public void testFindMainWindow() throws Exception {
         final TestAppWindowToken token = new TestAppWindowToken();
@@ -93,5 +125,13 @@ public class AppWindowTokenTests {
         boolean hasWindow(WindowState w) {
             return mChildren.contains(w);
         }
+
+        WindowState getFirstChild() {
+            return mChildren.getFirst();
+        }
+
+        WindowState getLastChild() {
+            return mChildren.getLast();
+        }
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
index 546c7da0a013e..5326a192bf73f 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
@@ -41,9 +41,8 @@ import static org.mockito.Mockito.mock;
 /**
  * Tests for the {@link WindowState} class.
  *
- * Build: mmma -j32 frameworks/base/services/tests/servicestests
- * Install: adb install -r out/target/product/$TARGET_PRODUCT/data/app/FrameworksServicesTests/FrameworksServicesTests.apk
- * Run: adb shell am instrument -w -e class com.android.server.wm.WindowTokenTests com.android.frameworks.servicestests/android.support.test.runner.AndroidJUnitRunner
+ * Build/Install/Run:
+ *  bit FrameworksServicesTests:com.android.server.wm.WindowTokenTests
  */
 @SmallTest
 @Presubmit