(not for review) Add overhang resource

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 9956f4c7359887d8c3fa44f720f6c7177abf780d..b600d0ec8592417f396188a61f4770c07f3a6988 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -38,6 +38,7 @@
 #include "cc/trees/single_thread_proxy.h"
 #include "cc/trees/thread_proxy.h"
 #include "cc/trees/tree_synchronizer.h"
+#include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/size_conversions.h"
 
 namespace {
@@ -196,6 +197,29 @@ LayerTreeHost::OnCreateAndInitializeOutputSurfaceAttempted(bool success) {
           contents_texture_manager_->CreateTexture(gfx::Size(), GL_RGBA);
     }
 
+    // Okay, this should be done in a more principled way...
+    if (1) {
+      // So this is supposed to come from a header file (but only on platforms
+      // that have an overhang...).
+      int IDR_IDR_OVERHANG_PATTERN = 4740;
+      // And this can't be called in unit tests...
+      const gfx::Image& overhang_image =
+          ui::ResourceBundle::GetSharedInstance().GetImageNamed(
+              IDR_IDR_OVERHANG_PATTERN);
+      overhang_bitmap_ = UIResourceBitmap::Create(
+          new uint8_t[overhang_image.Size().width() *
+                      overhang_image.Size().height() * 4],
+          UIResourceBitmap::RGBA8,
+          UIResourceBitmap::Repeat,
+          overhang_image.Size());
+      overhang_image.CopySkBitmap()->copyPixelsTo(
+          overhang_bitmap_->GetPixels(),
+          overhang_image.Size().width() * overhang_image.Size().height() * 4,
+          overhang_image.Size().width() * 4,
+          false);
+      overhang_ui_resource_ = ScopedUIResource::Create(this, overhang_bitmap_);
+    }
+
     client_->DidInitializeOutputSurface(true);
     return CreateSucceeded;
   }
@@ -369,6 +393,10 @@ void LayerTreeHost::FinishCommitOnImplThread(LayerTreeHostImpl* host_impl) {
     if (!settings_.impl_side_painting)
       sync_tree->ProcessUIResourceRequestQueue();
   }
+  if (overhang_ui_resource_ && overhang_bitmap_) {
+    host_impl->SetOverhangUIResource(
+        overhang_ui_resource_->id(), overhang_bitmap_->GetSize());
+  }
 
   DCHECK(!sync_tree->ViewportSizeInvalid());