Stop reloading wallpaper bitmap

Typo in ImageWallpaper made a dimension check incorrect.

Issue#7373200 pause when toggling between All Apps and Home screen; Home button stays illuminated for a long time

Change-Id: I82763ac8c9ed564eba904f552975ab20c8aef932

Author: chethaase

packages/SystemUI/src/com/android/systemui/ImageWallpaper.java

@@ -327,7 +327,7 @@ void drawFrameLocked() {
             mLastRotation = newRotation;
 
             // Load bitmap if it is not yet loaded or if it was loaded at a different size
-            if (mBackground == null || dw != mBackgroundWidth || dw != mBackgroundHeight) {
+            if (mBackground == null || dw != mBackgroundWidth || dh != mBackgroundHeight) {
                 if (DEBUG) {
                     Log.d(TAG, "Reloading bitmap");
                 }