Fix IME window can't show on Simulated display

CL Icfd66689dad4b782c50b56a515194dd138d3b280 introduced
WindowManagerInternal#shouldShowIme for IMMS to check if the display can
show IME window, which just calling DisplayWindowSettings#shouldShowIme.

That will missed Simulated display use case & we should use WMS#shouldShowIme
since we have already implemented force desktop mode check for simulated
display with combined DisplayWindowSettings#shouldShowIme in above CL.

Correct the API usage to fix the issue.

Fix: 131921175
Fix: 129443632

Test: atest MultiDisplaySystemDecorationTests
Test: atest DisplayWindowSettingsTests#testShouldShowImeWithinForceDesktopMode
Test: manual as below steps:
 1. adb shell settings put global force_desktop_mode_on_external_displays 1
 2. adb shell settings put global overlay_display_devices 1080x1920/320
 3. adb reboot, make sure simulated display overlaid on device.
 4. By using a Bluetooth mouse or a USB mouse, launch any Activity on
    simulated display that has an input field.
 5. Click that input field to see if IME window can shown simulated display.

Change-Id: I5b592f7152dffb12826c6cbd8ab466fcf1392fb7

services/core/java/com/android/server/wm/WindowManagerService.java

@@ -7426,8 +7426,7 @@ public class WindowManagerService extends IWindowManager.Stub
         @Override
         public boolean shouldShowIme(int displayId) {
             synchronized (mGlobalLock) {
-                final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
-                return mDisplayWindowSettings.shouldShowImeLocked(displayContent);
+                return WindowManagerService.this.shouldShowIme(displayId);
             }
         }
     }

services/tests/wmtests/src/com/android/server/wm/DisplayWindowSettingsTests.java

@@ -51,6 +51,7 @@ import android.view.Surface;
 import androidx.test.filters.SmallTest;
 
 import com.android.dx.mockito.inline.extended.ExtendedMockito;
+import com.android.server.LocalServices;
 import com.android.server.policy.WindowManagerPolicy;
 
 import org.junit.After;
@@ -588,6 +589,23 @@ public class DisplayWindowSettingsTests extends WindowTestsBase {
                 getStoredDisplayAttributeValue("shouldShowIme"));
     }
 
+    @Test
+    public void testShouldShowImeWithinForceDesktopMode() {
+        try {
+            // Presume display enabled force desktop mode from developer options.
+            final DisplayContent dc = createMockSimulatedDisplay();
+            mWm.setForceDesktopModeOnExternalDisplays(true);
+            final WindowManagerInternal wmInternal = LocalServices.getService(
+                    WindowManagerInternal.class);
+            // Make sure WindowManagerInter#shouldShowIme as true is due to
+            // mForceDesktopModeOnExternalDisplays as true.
+            assertFalse(mWm.mDisplayWindowSettings.shouldShowImeLocked(dc));
+            assertTrue(wmInternal.shouldShowIme(dc.getDisplayId()));
+        } finally {
+            mWm.setForceDesktopModeOnExternalDisplays(false);
+        }
+    }
+
     /**
      * Prepares display settings and stores in {@link #mStorage}. Uses provided display identifier
      * and stores windowingMode=WINDOWING_MODE_PINNED.

services/tests/wmtests/src/com/android/server/wm/WindowTestsBase.java

@@ -19,6 +19,7 @@ package com.android.server.wm;
 import static android.app.AppOpsManager.OP_NONE;
 import static android.app.WindowConfiguration.ACTIVITY_TYPE_STANDARD;
 import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
+import static android.os.Process.SYSTEM_UID;
 import static android.view.Display.DEFAULT_DISPLAY;
 import static android.view.DisplayAdjustments.DEFAULT_DISPLAY_ADJUSTMENTS;
 import static android.view.View.VISIBLE;
@@ -445,4 +446,13 @@ class WindowTestsBase {
             return new WindowTestUtils.TestWindowState(mWm, mMockSession, mIWindow, attrs, token);
         }
     }
+
+    /** Creates a {@link DisplayContent} as parts of simulate display info for test. */
+    DisplayContent createMockSimulatedDisplay() {
+        DisplayInfo displayInfo = new DisplayInfo();
+        displayInfo.copyFrom(mDisplayInfo);
+        displayInfo.type = Display.TYPE_VIRTUAL;
+        displayInfo.ownerUid = SYSTEM_UID;
+        return createNewDisplay(displayInfo);
+    }
 }