[Android] Harden overscroll resource allocation

It appears that overscroll scenarios are not covered by existing integration
tests on Android.  Add such a test while cleaning up an overscroll-related
code path for loading potentially non-existent resources.

BUG=341406

Review URL: https://codereview.chromium.org/210623002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@259474 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 2 insertions, 1 deletions

diff --git a/ui/android/java/src/org/chromium/ui/gfx/BitmapHelper.java b/ui/android/java/src/org/chromium/ui/gfx/BitmapHelper.java
index dd04217..5c4549c 100644
--- a/ui/android/java/src/org/chromium/ui/gfx/BitmapHelper.java
+++ b/ui/android/java/src/org/chromium/ui/gfx/BitmapHelper.java
@@ -39,14 +39,15 @@ public class BitmapHelper {
                                                  int reqHeight) {
         Resources res = Resources.getSystem();
         int resId = res.getIdentifier(name, null, null);
+        if (resId == 0) return null;
 
         final BitmapFactory.Options options = new BitmapFactory.Options();
         options.inJustDecodeBounds = true;
         BitmapFactory.decodeResource(res, resId, options);
 
         options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
-
         options.inJustDecodeBounds = false;
+        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
         return BitmapFactory.decodeResource(res, resId, options);
     }