diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 0d160a94c4091..eedf5e21826c3 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -215,6 +215,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
     boolean mLastWasImTarget;
 
     boolean mWindowAttributesChanged = false;
+    int mWindowAttributesChangesFlag = 0;
 
     // These can be accessed by any thread, must be protected with a lock.
     // Surface can never be reassigned or cleared (use Surface.clear()).
@@ -439,6 +440,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
                 mSoftInputMode = attrs.softInputMode;
                 mWindowAttributesChanged = true;
+                mWindowAttributesChangesFlag = WindowManager.LayoutParams.EVERYTHING_CHANGED;
                 mAttachInfo.mRootView = view;
                 mAttachInfo.mScalingRequired = mTranslator != null;
                 mAttachInfo.mApplicationScale =
@@ -640,7 +642,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             // preserve compatible window flag if exists.
             int compatibleWindowFlag =
                 mWindowAttributes.flags & WindowManager.LayoutParams.FLAG_COMPATIBLE_WINDOW;
-            mWindowAttributes.copyFrom(attrs);
+            mWindowAttributesChangesFlag = mWindowAttributes.copyFrom(attrs);
             mWindowAttributes.flags |= compatibleWindowFlag;
             
             if (newView) {
@@ -844,14 +846,17 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                 || mNewSurfaceNeeded;
 
         WindowManager.LayoutParams params = null;
+        int windowAttributesChanges = 0;
         if (mWindowAttributesChanged) {
             mWindowAttributesChanged = false;
             surfaceChanged = true;
             params = lp;
+            windowAttributesChanges = mWindowAttributesChangesFlag;
         }
         CompatibilityInfo compatibilityInfo = mCompatibilityInfo.get();
         if (compatibilityInfo.supportsScreen() == mLastInCompatMode) {
             params = lp;
+            windowAttributesChanges |= WindowManager.LayoutParams.BUFFER_CHANGED;
             fullRedrawNeeded = true;
             mLayoutRequested = true;
             if (mLastInCompatMode) {
@@ -862,6 +867,9 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                 mLastInCompatMode = true;
             }
         }
+        
+        mWindowAttributesChangesFlag = 0;
+        
         Rect frame = mWinFrame;
         if (mFirst) {
             fullRedrawNeeded = true;
@@ -1041,6 +1049,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                     || attachInfo.mSystemUiVisibility != oldVis
                     || attachInfo.mHasSystemUiListeners) {
                 params = lp;
+                windowAttributesChanges |= WindowManager.LayoutParams.BUFFER_CHANGED;
             }
         }
 
@@ -1066,6 +1075,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                             ~WindowManager.LayoutParams.SOFT_INPUT_MASK_ADJUST) |
                             resizeMode;
                     params = lp;
+                    windowAttributesChanges |= WindowManager.LayoutParams.BUFFER_CHANGED;
                 }
             }
         }
@@ -1362,7 +1372,8 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                 }
             }
 
-            if (hwInitialized || ((windowShouldResize || params != null) &&
+            if (hwInitialized || ((windowShouldResize || (params != null &&
+                    (windowAttributesChanges & WindowManager.LayoutParams.BUFFER_CHANGED) != 0)) &&
                     mAttachInfo.mHardwareRenderer != null &&
                     mAttachInfo.mHardwareRenderer.isEnabled())) {
                 mAttachInfo.mHardwareRenderer.setup(mWidth, mHeight);
@@ -1637,6 +1648,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             // Need to make sure we re-evaluate the window attributes next
             // time around, to ensure the window has the correct format.
             mWindowAttributesChanged = true;
+            mWindowAttributesChangesFlag = 0;
             requestLayout();
         }
     }
diff --git a/core/java/android/view/WindowManager.java b/core/java/android/view/WindowManager.java
index fb31e7d8f205c..96c151248fa85 100644
--- a/core/java/android/view/WindowManager.java
+++ b/core/java/android/view/WindowManager.java
@@ -1252,7 +1252,11 @@ public interface WindowManager extends ViewManager {
         public static final int INPUT_FEATURES_CHANGED = 1<<15;
         /** {@hide} */
         public static final int PRIVATE_FLAGS_CHANGED = 1<<16;
-    
+        /** {@hide} */
+        public static final int BUFFER_CHANGED = 1<<17;
+        /** {@hide} */
+        public static final int EVERYTHING_CHANGED = 0xffffffff;
+
         // internal buffer to backup/restore parameters under compatibility mode.
         private int[] mCompatibilityParamsBackup = null;
         
@@ -1261,11 +1265,11 @@ public interface WindowManager extends ViewManager {
     
             if (width != o.width) {
                 width = o.width;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (height != o.height) {
                 height = o.height;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (x != o.x) {
                 x = o.x;
@@ -1277,19 +1281,19 @@ public interface WindowManager extends ViewManager {
             }
             if (horizontalWeight != o.horizontalWeight) {
                 horizontalWeight = o.horizontalWeight;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (verticalWeight != o.verticalWeight) {
                 verticalWeight = o.verticalWeight;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (horizontalMargin != o.horizontalMargin) {
                 horizontalMargin = o.horizontalMargin;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (verticalMargin != o.verticalMargin) {
                 verticalMargin = o.verticalMargin;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (type != o.type) {
                 type = o.type;
@@ -1297,7 +1301,7 @@ public interface WindowManager extends ViewManager {
             }
             if (flags != o.flags) {
                 flags = o.flags;
-                changes |= FLAGS_CHANGED;
+                changes |= FLAGS_CHANGED | BUFFER_CHANGED;
             }
             if (privateFlags != o.privateFlags) {
                 privateFlags = o.privateFlags;
@@ -1309,11 +1313,11 @@ public interface WindowManager extends ViewManager {
             }
             if (gravity != o.gravity) {
                 gravity = o.gravity;
-                changes |= LAYOUT_CHANGED;
+                changes |= LAYOUT_CHANGED | BUFFER_CHANGED;
             }
             if (format != o.format) {
                 format = o.format;
-                changes |= FORMAT_CHANGED;
+                changes |= FORMAT_CHANGED | BUFFER_CHANGED;
             }
             if (windowAnimations != o.windowAnimations) {
                 windowAnimations = o.windowAnimations;
@@ -1352,7 +1356,7 @@ public interface WindowManager extends ViewManager {
     
             if (screenOrientation != o.screenOrientation) {
                 screenOrientation = o.screenOrientation;
-                changes |= SCREEN_ORIENTATION_CHANGED;
+                changes |= SCREEN_ORIENTATION_CHANGED | BUFFER_CHANGED;
             }
 
             if (systemUiVisibility != o.systemUiVisibility