Make BitmapRegionDecoder succeed on invalid requests

include/codec/SkAndroidCodec.h

Index: include/codec/SkAndroidCodec.h
diff --git a/include/codec/SkAndroidCodec.h b/include/codec/SkAndroidCodec.h
index f979886a43ec33c573de3553b49651a8a06d7025..9e12afb3607240dfcb2c51fc25b680277e1379a6 100644
--- a/include/codec/SkAndroidCodec.h
+++ b/include/codec/SkAndroidCodec.h
@@ -42,6 +42,28 @@ public:
      */
     static SkAndroidCodec* NewFromData(SkData*, SkPngChunkReader* = NULL);
 
+    /**
+     *  @param requestedColorType Color type requested by the client
+     *  @param suggestedColorType Color type suggested by SkAndroidCodec
+     *  @param suggestedAlphaType Alpha type suggested by SkAndroidCodec
+     *
+     *  @return If it is possible to decode to requestedColorType, this returns
+     *          requestedColorType.  Otherwise, this returns kN32_SkColorType.
+     */
+    static SkColorType FixRequestedColorType(SkColorType requestedColorType,
+            SkColorType suggestedColorType, SkAlphaType suggestedAlphaType);
+
+    /**
+     *  @param requestedUnpremul  Indicates if the client requested
+     *                            unpremultiplied output
+     *  @param suggestedAlphaType Alpha type suggested by SkAndroidCodec
+     *
+     *  @return Returns the appropriate alpha type to decode to.  If the image
+     *          has alpha, the value of requestedUnpremul will be honored.
+     */
+    static SkAlphaType FixRequestedAlphaType(bool requestedUnpremul,
+            SkAlphaType suggestedAlphaType);
+
     virtual ~SkAndroidCodec() {}