Initialize FastBitmapDrawable bounds with default bitmap dimensions.

Change-Id: Ida9603e35b242a581b9401c6440875cd511725a1
diff --git a/src/com/android/launcher3/FastBitmapDrawable.java b/src/com/android/launcher3/FastBitmapDrawable.java
index 83be143..85e9020 100644
--- a/src/com/android/launcher3/FastBitmapDrawable.java
+++ b/src/com/android/launcher3/FastBitmapDrawable.java
@@ -32,6 +32,7 @@
     FastBitmapDrawable(Bitmap b) {
         mAlpha = 255;
         mBitmap = b;
+        setBounds(0, 0, b.getWidth(), b.getHeight());
     }
 
     @Override