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

Currently some methods mutate the class, and some return a new value, requiring
API users to know what kind of method they are calling each time, and making
inconsistent code. For example:

gfx::Rect rect;
rect.Inset(1, 1, 1, 1);
rect = rect.Intersect(other_rect);
rect.Offset(1, 1);

Instead of:

gfx::Rect rect;
rect.Inset(1, 1, 1, 1);
rect.Intersect(other_rect);
rect.Offset(1, 1);

We could go either way - making the class immutable or all methods return a new
instance - but I believe it is better to instead make all methods mutate the
class. This allows for shorter lines of code by avoiding having to repeat the
object's name twice in order to change it.

This patch changes gfx::Rect classes and all the callsites that uses these
methods. It should make no change in behaviour, so no new tests added.

R=sky
BUG=147395

Review URL: https://codereview.chromium.org/11110004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@163579 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 4 deletions

diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index a8d05a8..69bb0cf 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -852,8 +852,9 @@ void RenderWidgetHostViewMac::CopyFromCompositingSurface(
   gfx::Rect src_gl_subrect = src_subrect;
   src_gl_subrect.set_y(GetViewBounds().height() - src_subrect.bottom());
 
-  gfx::Rect src_pixel_gl_subrect =
-      gfx::ToEnclosingRect(src_gl_subrect.Scale(scale));
+  gfx::RectF scaled_src_gl_subrect = src_gl_subrect;
+  scaled_src_gl_subrect.Scale(scale);
+  gfx::Rect src_pixel_gl_subrect = gfx::ToEnclosingRect(scaled_src_gl_subrect);
   compositing_iosurface_->CopyTo(
       src_pixel_gl_subrect,
       dst_pixel_size,
@@ -1118,7 +1119,7 @@ gfx::Rect RenderWidgetHostViewMac::GetFirstRectForCompositionRange(
   *actual_range = ui::Range(range.start(), end_idx);
   gfx::Rect rect = composition_bounds_[range.start()];
   for (size_t i = range.start() + 1; i < end_idx; ++i) {
-    rect = rect.Union(composition_bounds_[i]);
+    rect.Union(composition_bounds_[i]);
   }
   return rect;
 }
@@ -2269,7 +2270,8 @@ void RenderWidgetHostViewMac::SetTextInputActive(bool active) {
     // smaller and the renderer hasn't yet repainted.
     int yOffset = NSHeight([self bounds]) - backingStore->size().height();
 
-    gfx::Rect paintRect = bitmapRect.Intersect(damagedRect);
+    gfx::Rect paintRect = bitmapRect;
+    paintRect.Intersect(damagedRect);
     if (!paintRect.IsEmpty()) {
       // if we have a CGLayer, draw that into the window
       if (backingStore->cg_layer()) {