Fix merged bitmap mesh generation and reenable merging

bug:26793764
bug:26569206
Change-Id: I54628e99b61f58f5726a387ea3599c29695c0efc

libs/hwui/BakedOpDispatcher.cpp

@@ -61,7 +61,10 @@ void BakedOpDispatcher::onMergedBitmapOps(BakedOpRenderer& renderer,
     for (size_t i = 0; i < opList.count; i++) {
         const BakedOpState& state = *(opList.states[i]);
         TextureVertex* rectVerts = &vertices[i * 4];
-        Rect opBounds = state.computedState.clippedBounds;
+
+        // calculate unclipped bounds, since they'll determine texture coordinates
+        Rect opBounds = state.op->unmappedBounds;
+        state.computedState.transform.mapRect(opBounds);
         if (CC_LIKELY(state.computedState.transform.isPureTranslate())) {
             // pure translate, so snap (same behavior as onBitmapOp)
             opBounds.snapToPixelBoundaries();

libs/hwui/FrameBuilder.cpp

@@ -517,10 +517,6 @@ void FrameBuilder::deferBitmapOp(const BitmapOp& op) {
     BakedOpState* bakedState = tryBakeOpState(op);
     if (!bakedState) return; // quick rejected
 
-    currentLayer().deferUnmergeableOp(mAllocator, bakedState, OpBatchType::Bitmap);
-
-    // TODO: Fix this ( b/26569206 )
-/*
     // Don't merge non-simply transformed or neg scale ops, SET_TEXTURE doesn't handle rotation
     // Don't merge A8 bitmaps - the paint's color isn't compared by mergeId, or in
     // MergingDrawBatch::canMergeWith()
@@ -535,7 +531,6 @@ void FrameBuilder::deferBitmapOp(const BitmapOp& op) {
     } else {
         currentLayer().deferUnmergeableOp(mAllocator, bakedState, OpBatchType::Bitmap);
     }
-*/
 }
 
 void FrameBuilder::deferBitmapMeshOp(const BitmapMeshOp& op) {

libs/hwui/tests/unit/FrameBuilderTests.cpp

@@ -216,8 +216,7 @@ TEST(FrameBuilder, simpleBatching) {
             << "Expect number of ops = 2 * loop count";
 }
 
-// TODO: Disabled due to b/26793764
-TEST(FrameBuilder, DISABLED_clippedMerging) {
+TEST(FrameBuilder, clippedMerging) {
     class ClippedMergingTestRenderer : public TestRendererBase {
     public:
         void onMergedBitmapOps(const MergedBakedOpList& opList) override {