cc: Don't consider HUD layer for touches

cc/layer_tree_host_common_unittest.cc

Index: cc/layer_tree_host_common_unittest.cc
diff --git a/cc/layer_tree_host_common_unittest.cc b/cc/layer_tree_host_common_unittest.cc
index 3724971481965ee38f3ab54f8f52b95460c83997..2b9c0ff4fd2f94f51fd8f665d8b8a90003423011 100644
--- a/cc/layer_tree_host_common_unittest.cc
+++ b/cc/layer_tree_host_common_unittest.cc
@@ -6,9 +6,11 @@
 
 #include "cc/content_layer.h"
 #include "cc/content_layer_client.h"
+#include "cc/heads_up_display_layer_impl.h"
 #include "cc/layer.h"
 #include "cc/layer_animation_controller.h"
 #include "cc/layer_impl.h"
+#include "cc/layer_tree_impl.h"
 #include "cc/math_util.h"
 #include "cc/proxy.h"
 #include "cc/single_thread_proxy.h"
@@ -2962,6 +2964,58 @@ TEST(LayerTreeHostCommonTest, verifyHitTestingForSingleLayer)
     EXPECT_EQ(12345, resultLayer->id());
 }
 
+TEST(LayerTreeHostCommonTest, verifyHitTestingForSingleLayerAndHud)
+{
+    FakeImplProxy proxy;
+    FakeLayerTreeHostImpl hostImpl(&proxy);
+    scoped_ptr<LayerImpl> root = LayerImpl::create(hostImpl.activeTree(), 12345);
+    scoped_ptr<HeadsUpDisplayLayerImpl> hud = HeadsUpDisplayLayerImpl::create(hostImpl.activeTree(), 11111);
+
+    gfx::Transform identityMatrix;
+    gfx::PointF anchor(0, 0);

[danakj, 2013/02/19 20:08:12]

0.f

+    gfx::PointF position(0, 0);

[danakj, 2013/02/19 20:08:12]

0.f

+    gfx::Size bounds(100, 100);
+    setLayerPropertiesForTesting(root.get(), identityMatrix, identityMatrix, anchor, position, bounds, false);
+    root->setDrawsContent(true);
+
+    // Create hud and add it as a child of root.
+    gfx::Size hudBounds(200, 200);
+    hud->setForceRenderSurface(true);

[danakj, 2013/02/19 20:08:12]

why this? the hud doesn't own a surface in production.

+    setLayerPropertiesForTesting(hud.get(), identityMatrix, identityMatrix, anchor, position, hudBounds, false);
+    hud->setDrawsContent(true);

[danakj, 2013/02/19 20:08:12]

not needed for the hud. it always draws content.

+
+    hostImpl.activeTree()->set_hud_layer(hud.get());

[danakj, 2013/02/19 20:08:12]

I really dislike that this unit test is now needing to know about so many
classes and their APIs.

I think the best way to write this test would be to make a test in
layer_tree_host_unittest.cc, make a hud layer on the main thread, and do the hit
testing stuff in the drawLayersOnImplTread() function.

+    root->addChild(hud.PassAs<LayerImpl>());
+
+    std::vector<LayerImpl*> renderSurfaceLayerList;
+    int dummyMaxTextureSize = 512;
+    LayerTreeHostCommon::calculateDrawProperties(root.get(), hudBounds, 1, 1, dummyMaxTextureSize, false, renderSurfaceLayerList, false);
+
+    // Sanity check the scenario we just created.
+    ASSERT_EQ(2u, renderSurfaceLayerList.size());
+    ASSERT_EQ(2u, root->renderSurface()->layerList().size());
+
+    // Hit testing for a point inside HUD, but outside root should return null
+    gfx::Point testPoint(101, 101);
+    LayerImpl* resultLayer = LayerTreeHostCommon::findLayerThatIsHitByPoint(testPoint, renderSurfaceLayerList);
+    EXPECT_FALSE(resultLayer);
+
+    testPoint = gfx::Point(-1, -1);
+    resultLayer = LayerTreeHostCommon::findLayerThatIsHitByPoint(testPoint, renderSurfaceLayerList);
+    EXPECT_FALSE(resultLayer);
+
+    // Hit testing for a point inside should return the root layer, never the HUD layer.
+    testPoint = gfx::Point(1, 1);
+    resultLayer = LayerTreeHostCommon::findLayerThatIsHitByPoint(testPoint, renderSurfaceLayerList);
+    ASSERT_TRUE(resultLayer);
+    EXPECT_EQ(12345, resultLayer->id());
+
+    testPoint = gfx::Point(99, 99);
+    resultLayer = LayerTreeHostCommon::findLayerThatIsHitByPoint(testPoint, renderSurfaceLayerList);
+    ASSERT_TRUE(resultLayer);
+    EXPECT_EQ(12345, resultLayer->id());
+}
+
 TEST(LayerTreeHostCommonTest, verifyHitTestingForUninvertibleTransform)
 {
     FakeImplProxy proxy;