Allow CanvasSkia to bind to an existing SkCanvas.

views/controls/tree/tree_view.cc

Index: views/controls/tree/tree_view.cc
diff --git a/views/controls/tree/tree_view.cc b/views/controls/tree/tree_view.cc
index 078ee20ea719784836e746f5d108d04232d43329..80313ed64840b54b2e603770a3a56c9b763ae527 100644
--- a/views/controls/tree/tree_view.cc
+++ b/views/controls/tree/tree_view.cc
@@ -699,7 +699,7 @@ HIMAGELIST TreeView::CreateImageList() {
           model_images[i].height() != height) {
         gfx::CanvasSkia canvas(width, height, false);
         // Make the background completely transparent.
-        canvas.drawColor(SK_ColorBLACK, SkXfermode::kClear_Mode);
+        canvas.sk_canvas()->drawColor(SK_ColorBLACK, SkXfermode::kClear_Mode);
 
         // Draw our icons into this canvas.
         int height_offset = (height - model_images[i].height()) / 2;
@@ -752,7 +752,7 @@ LRESULT CALLBACK TreeView::TreeWndProc(HWND window,
       if (canvas.isEmpty())
         return 0;
 
-      HDC dc = skia::BeginPlatformPaint(&canvas);
+      HDC dc = skia::BeginPlatformPaint(canvas.sk_canvas());
       if (base::i18n::IsRTL()) {
         // gfx::CanvasSkia ends up configuring the DC with a mode of
         // GM_ADVANCED. For some reason a graphics mode of ADVANCED triggers
@@ -786,7 +786,7 @@ LRESULT CALLBACK TreeView::TreeWndProc(HWND window,
         // over we copy the right bits.
         SetViewportOrgEx(dc, 0, 0, NULL);
       }
-      skia::EndPlatformPaint(&canvas);
+      skia::EndPlatformPaint(canvas.sk_canvas());
       return 0;
     }