cc: Fix hit-testing in zero-opacity layers.

cc/trees/occlusion_tracker_unittest.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/occlusion_tracker.h"
 
 #include "cc/animation/layer_animation_controller.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/overdraw_metrics.h"
 #include "cc/layers/layer.h"
@@ skipping 3988 matching lines @@
 
     EXPECT_EQ(gfx::Rect().ToString(),
               occlusion.occlusion_from_outside_target().ToString());
     EXPECT_EQ(gfx::Rect().ToString(),
               occlusion.occlusion_from_inside_target().ToString());
   }
 };
 
 ALL_OCCLUSIONTRACKER_TEST(OcclusionTrackerTestEmptyEventLayerDoesNotOcclude)
 
+template <class Types>
+class OcclusionTrackerTestZeroOpacityLayerDoesNotOcclude
+    : public OcclusionTrackerTest<Types> {
+ protected:
+  explicit OcclusionTrackerTestZeroOpacityLayerDoesNotOcclude(bool opaque)
+      : OcclusionTrackerTest<Types>(opaque) {}
+  void RunMyTest() {
+    typename Types::ContentLayerType* root = this->CreateRoot(
+        this->identity_matrix, gfx::Point(), gfx::Size(400, 400));
+    typename Types::ContentLayerType* zero_opacity_layer =
+        this->CreateDrawingLayer(root, this->identity_matrix, gfx::Point(),
+                                 gfx::Size(200, 200), true);
+    this->SetDrawsContent(zero_opacity_layer, false);
+    zero_opacity_layer->SetTouchEventHandlerRegion(gfx::Rect(10, 10, 10, 10));
+
+    this->CalcDrawEtc(root);
+
+    TestOcclusionTrackerWithClip<typename Types::LayerType,
+                                 typename Types::RenderSurfaceType> occlusion(
+        gfx::Rect(0, 0, 1000, 1000), false);
+
+    this->VisitLayer(zero_opacity_layer, &occlusion);
+
+    EXPECT_EQ(gfx::Rect().ToString(),
+              occlusion.occlusion_from_outside_target().ToString());
+    EXPECT_EQ(gfx::Rect().ToString(),
+              occlusion.occlusion_from_inside_target().ToString());
+  }
+};
+
+ALL_OCCLUSIONTRACKER_TEST(OcclusionTrackerTestZeroOpacityLayerDoesNotOcclude);
+
 }  // namespace
 }  // namespace cc