MD Buttons: Don't add layers for hidden -> hidden transitions.

ui/views/animation/test/test_ink_drop_host.cc

 // Copyright 2015 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 "ui/views/animation/test/test_ink_drop_host.h"
 
 #include "base/memory/ptr_util.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/views/animation/ink_drop_highlight.h"
 #include "ui/views/animation/square_ink_drop_ripple.h"
@@ skipping 64 matching lines @@
 
  private:
   std::unique_ptr<test::InkDropHighlightTestApi> test_api_;
 
   DISALLOW_COPY_AND_ASSIGN(TestInkDropHighlight);
 };
 
 }  // namespace
 
 TestInkDropHost::TestInkDropHost()
-    : num_ink_drop_layers_(0),
+    : num_ink_drop_layers_added_(0),
+      num_ink_drop_layers_removed_(0),
       should_show_highlight_(false),
       ripple_overrides_highlight_(true),
       disable_timers_for_test_(false) {}
 
 TestInkDropHost::~TestInkDropHost() {}
 
 void TestInkDropHost::AddInkDropLayer(ui::Layer* ink_drop_layer) {
-  ++num_ink_drop_layers_;
+  ++num_ink_drop_layers_added_;
 }
 
 void TestInkDropHost::RemoveInkDropLayer(ui::Layer* ink_drop_layer) {
-  --num_ink_drop_layers_;
+  ++num_ink_drop_layers_removed_;
 }
 
 std::unique_ptr<InkDropRipple> TestInkDropHost::CreateInkDropRipple() const {
   gfx::Size size(10, 10);
   std::unique_ptr<InkDropRipple> ripple(
       new TestInkDropRipple(size, 5, size, 5, gfx::Point(), SK_ColorBLACK,
                             0.175f, ripple_overrides_highlight_));
   if (disable_timers_for_test_)
     ripple->GetTestApi()->SetDisableAnimationTimers(true);
   return ripple;
 }
 
 std::unique_ptr<InkDropHighlight> TestInkDropHost::CreateInkDropHighlight()
     const {
   std::unique_ptr<InkDropHighlight> highlight;
   if (should_show_highlight_) {
     highlight.reset(new TestInkDropHighlight(gfx::Size(10, 10), 4,
                                              gfx::PointF(), SK_ColorBLACK));
     if (disable_timers_for_test_)
       highlight->GetTestApi()->SetDisableAnimationTimers(true);
   }
   return highlight;
 }
 
 }  // namespace views