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

2 files changed, 6 insertions, 7 deletions

diff --git a/ui/views/animation/bounds_animator.cc b/ui/views/animation/bounds_animator.cc
index 2c3fd05..037b9d6 100644
--- a/ui/views/animation/bounds_animator.cc
+++ b/ui/views/animation/bounds_animator.cc
@@ -235,14 +235,12 @@ void BoundsAnimator::AnimationProgressed(const Animation* animation) {
   gfx::Rect new_bounds =
       animation->CurrentValueBetween(data.start_bounds, data.target_bounds);
   if (new_bounds != view->bounds()) {
-    gfx::Rect total_bounds = new_bounds.Union(view->bounds());
+    gfx::Rect total_bounds = view->bounds();
+    total_bounds.Union(new_bounds);
 
     // Build up the region to repaint in repaint_bounds_. We'll do the repaint
     // when all animations complete (in AnimationContainerProgressed).
-    if (repaint_bounds_.IsEmpty())
-      repaint_bounds_ = total_bounds;
-    else
-      repaint_bounds_ = repaint_bounds_.Union(total_bounds);
+    repaint_bounds_.Union(total_bounds);
 
     view->SetBoundsRect(new_bounds);
   }
diff --git a/ui/views/animation/bounds_animator_unittest.cc b/ui/views/animation/bounds_animator_unittest.cc
index 93b13b5..2dbfc48 100644
--- a/ui/views/animation/bounds_animator_unittest.cc
+++ b/ui/views/animation/bounds_animator_unittest.cc
@@ -76,7 +76,7 @@ class TestView : public View {
     if (dirty_rect_.IsEmpty())
       dirty_rect_ = r;
     else
-      dirty_rect_ = dirty_rect_.Union(r);
+      dirty_rect_.Union(r);
   }
 
   const gfx::Rect& dirty_rect() const { return dirty_rect_; }
@@ -129,7 +129,8 @@ TEST_F(BoundsAnimatorTest, AnimateViewTo) {
 
   // The parent should have been told to repaint as the animation progressed.
   // The resulting rect is the union of the original and target bounds.
-  EXPECT_EQ(target_bounds.Union(initial_bounds), parent()->dirty_rect());
+  target_bounds.Union(initial_bounds);
+  EXPECT_EQ(target_bounds, parent()->dirty_rect());
 }
 
 // Make sure an AnimationDelegate is deleted when canceled.