Reduce memory allocation and make small improvements.

Change-Id: Iac3f302454119de6363cd5cfb158619e739b0536
diff --git a/tests/src/com/android/gallery3d/ui/GLCanvasStub.java b/tests/src/com/android/gallery3d/ui/GLCanvasStub.java
index 17d520d..41de108 100644
--- a/tests/src/com/android/gallery3d/ui/GLCanvasStub.java
+++ b/tests/src/com/android/gallery3d/ui/GLCanvasStub.java
@@ -39,10 +39,10 @@
     public boolean clipRect(int left, int top, int right, int bottom) {
         throw new UnsupportedOperationException();
     }
-    public int save() {
+    public void save() {
         throw new UnsupportedOperationException();
     }
-    public int save(int saveFlags) {
+    public void save(int saveFlags) {
         throw new UnsupportedOperationException();
     }
     public void setBlendEnabled(boolean enabled) {}