cc: Fix impl-side painting rasterization at >1 contents scales

cc/picture.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 "base/debug/trace_event.h"
 #include "cc/content_layer_client.h"
 #include "cc/picture.h"
 #include "cc/rendering_stats.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "ui/gfx/rect_conversions.h"
@@ skipping 44 matching lines @@
   canvas->translate(SkFloatToScalar(-layer_rect_.x()),
                     SkFloatToScalar(-layer_rect_.y()));
 
   SkPaint paint;
   paint.setAntiAlias(false);
   paint.setXfermodeMode(SkXfermode::kClear_Mode);
   SkRect layer_skrect = SkRect::MakeXYWH(layer_rect_.x(),
                                          layer_rect_.y(),
                                          layer_rect_.width(),
                                          layer_rect_.height());
+  canvas->clipRect(layer_skrect);
   canvas->drawRect(layer_skrect, paint);
-  canvas->clipRect(layer_skrect);
 
   gfx::RectF opaque_layer_rect;
   base::TimeTicks beginPaintTime = base::TimeTicks::Now();
   painter->paintContents(canvas, layer_rect_, opaque_layer_rect);
   double delta = (base::TimeTicks::Now() - beginPaintTime).InSecondsF();
   stats.totalPaintTimeInSeconds += delta;
   stats.totalPixelsPainted += layer_rect_.width() *
                               layer_rect_.height();
 
   canvas->restore();
   picture_->endRecording();
 
   opaque_rect_ = gfx::ToEnclosedRect(opaque_layer_rect);
 }
 
 void Picture::Raster(SkCanvas* canvas) {
   TRACE_EVENT0("cc", "Picture::Raster");
   DCHECK(picture_);
   canvas->save();
   canvas->translate(layer_rect_.x(), layer_rect_.y());
   canvas->drawPicture(*picture_);
   canvas->restore();
 }
 
 }  // namespace cc