Make gfx::Rect class operations consistently mutate the class they are called on.

content/browser/renderer_host/backing_store_aura.cc

 // Copyright (c) 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 "content/browser/renderer_host/backing_store_aura.h"
 
 #include "content/browser/renderer_host/dip_util.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/public/browser/render_widget_host.h"
 #include "skia/ext/platform_canvas.h"
@@ skipping 73 matching lines @@
     TransportDIB::Id bitmap,
     const gfx::Rect& bitmap_rect,
     const std::vector<gfx::Rect>& copy_rects,
     float scale_factor,
     const base::Closure& completion_callback,
     bool* scheduled_completion_callback) {
   *scheduled_completion_callback = false;
   if (bitmap_rect.IsEmpty())
     return;
 
-  gfx::Rect pixel_bitmap_rect =
-      gfx::ToEnclosedRect(bitmap_rect.Scale(scale_factor));
+  gfx::RectF scaled_bitmap_rect = bitmap_rect;
+  scaled_bitmap_rect.Scale(scale_factor);
+  gfx::Rect pixel_bitmap_rect = gfx::ToEnclosedRect(scaled_bitmap_rect);
 
   const int width = pixel_bitmap_rect.width();
   const int height = pixel_bitmap_rect.height();
 
   if (width <= 0 || width > kMaxVideoLayerSize ||
       height <= 0 || height > kMaxVideoLayerSize)
     return;
 
   TransportDIB* dib = process->GetTransportDIB(bitmap);
   if (!dib)
     return;
 
   SkPaint copy_paint;
   copy_paint.setXfermodeMode(SkXfermode::kSrc_Mode);
 
   SkBitmap sk_bitmap;
   sk_bitmap.setConfig(SkBitmap::kARGB_8888_Config, width, height);
   sk_bitmap.setPixels(dib->memory());
   for (size_t i = 0; i < copy_rects.size(); i++) {
-    const gfx::Rect pixel_copy_rect =
-        gfx::ToEnclosingRect(copy_rects[i].Scale(scale_factor));
+    gfx::RectF scaled_copy_rect = copy_rects[i];
+    scaled_copy_rect.Scale(scale_factor);
+    const gfx::Rect pixel_copy_rect = gfx::ToEnclosingRect(scaled_copy_rect);
     int x = pixel_copy_rect.x() - pixel_bitmap_rect.x();
     int y = pixel_copy_rect.y() - pixel_bitmap_rect.y();
     SkIRect srcrect = SkIRect::MakeXYWH(x, y,
         pixel_copy_rect.width(),
         pixel_copy_rect.height());
 
+    gfx::RectF scaled_copy_dst_rect = copy_rects[i];
+    scaled_copy_dst_rect.Scale(device_scale_factor_);
     const gfx::Rect pixel_copy_dst_rect =
-        gfx::ToEnclosingRect(copy_rects[i].Scale(device_scale_factor_));
+        gfx::ToEnclosingRect(scaled_copy_dst_rect);
     SkRect dstrect = SkRect::MakeXYWH(
         SkIntToScalar(pixel_copy_dst_rect.x()),
         SkIntToScalar(pixel_copy_dst_rect.y()),
         SkIntToScalar(pixel_copy_dst_rect.width()),
         SkIntToScalar(pixel_copy_dst_rect.height()));
     canvas_.get()->drawBitmapRect(sk_bitmap, &srcrect, dstrect, &copy_paint);
   }
 }
 
 void BackingStoreAura::ScrollBackingStore(int dx, int dy,
                                           const gfx::Rect& clip_rect,
                                           const gfx::Size& view_size) {
-  gfx::Rect pixel_rect =
-      gfx::ToEnclosingRect(clip_rect.Scale(device_scale_factor_));
+  gfx::RectF scaled_clip_rect = clip_rect;
+  scaled_clip_rect.Scale(device_scale_factor_);
+  gfx::Rect pixel_rect = gfx::ToEnclosingRect(scaled_clip_rect);
   int pixel_dx = dx * device_scale_factor_;
   int pixel_dy = dy * device_scale_factor_;
 
   int x = std::min(pixel_rect.x(), pixel_rect.x() - pixel_dx);
   int y = std::min(pixel_rect.y(), pixel_rect.y() - pixel_dy);
   int w = pixel_rect.width() + abs(pixel_dx);
   int h = pixel_rect.height() + abs(pixel_dy);
   SkIRect rect = SkIRect::MakeXYWH(x, y, w, h);
   bitmap_.scrollRect(&rect, pixel_dx, pixel_dy);
 }
 
 bool BackingStoreAura::CopyFromBackingStore(const gfx::Rect& rect,
                                             skia::PlatformBitmap* output) {
   const int width =
       std::min(size().width(), rect.width()) * device_scale_factor_;
   const int height =
       std::min(size().height(), rect.height()) * device_scale_factor_;
   if (!output->Allocate(width, height, true))
     return false;
 
   SkIRect skrect = SkIRect::MakeXYWH(rect.x(), rect.y(), width, height);
   SkBitmap b;
   if (!canvas_->readPixels(skrect, &b))
     return false;
   SkCanvas(output->GetBitmap()).writePixels(b, rect.x(), rect.y());
   return true;
 }
 
 }  // namespace content