Revert of Remove ForceReclaimResources

ui/compositor/layer_unittest.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 "ui/compositor/layer.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
@@ skipping 1138 matching lines @@
   root->SetBounds(gfx::Rect(0, 0, 10, 10));
   root->SetVisible(true);
   WaitForCommit();
 
   gfx::Rect damaged_rect(0, 0, 5, 5);
   root->SchedulePaint(damaged_rect);
   EXPECT_EQ(damaged_rect, root->damaged_region_for_testing().bounds());
   WaitForCommit();
   EXPECT_TRUE(root->damaged_region_for_testing().IsEmpty());
 
-  // The texture mailbox has a reference from an in-flight texture layer.
-  // We clear the texture mailbox from the root layer and draw a new frame
-  // to ensure that the texture mailbox is released. We then draw a second
-  // frame to ensure that the mailbox's release callback has time to run.
-  root->SetShowSolidColorContent();
-  Draw();
-  Draw();
+  compositor()->SetRootLayer(nullptr);
+  root.reset();
+  WaitForCommit();
 }
 
 void ExpectRgba(int x, int y, SkColor expected_color, SkColor actual_color) {
   EXPECT_EQ(expected_color, actual_color)
       << "Pixel error at x=" << x << " y=" << y << "; "
       << "actual RGBA=("
       << SkColorGetR(actual_color) << ","
       << SkColorGetG(actual_color) << ","
       << SkColorGetB(actual_color) << ","
       << SkColorGetA(actual_color) << "); "
@@ skipping 1105 matching lines @@
   layer.set_name("foo");
   std::unique_ptr<base::trace_event::ConvertableToTraceFormat> debug_info =
       layer.TakeDebugInfo(nullptr);
   std::string trace_format("bar,");
   debug_info->AppendAsTraceFormat(&trace_format);
   std::string expected("bar,{\"layer_name\":\"foo\"}");
   EXPECT_EQ(expected, trace_format);
 }
 
 }  // namespace ui