Disable flaky LayerWithRealCompositorTest.ReportMetrics test on windows.

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 2192 matching lines @@
     report_called_ = true;
   }
 
  private:
   bool report_called_ = false;
   int value_ = -1;
 
   DISALLOW_COPY_AND_ASSIGN(TestMetricsReporter);
 };
 
+// TODO(crbug/709080): LayerWithRealCompositorTest.ReportMetrics is flaky on
+// Windows.
+#if defined(OS_WIN)
+#define MAYBE_ReportMetrics DISABLED_ReportMetrics
+#else
+#define MAYBE_ReportMetrics ReportMetrics
+#endif
+
 // Starts an animation and tests that incrementing compositor frame count can
 // be used to report animation smoothness metrics.
-TEST_F(LayerWithRealCompositorTest, ReportMetrics) {
+TEST_F(LayerWithRealCompositorTest, MAYBE_ReportMetrics) {
   std::unique_ptr<Layer> root(CreateLayer(LAYER_SOLID_COLOR));
   GetCompositor()->SetRootLayer(root.get());
   LayerAnimator* animator = root->GetAnimator();
   std::unique_ptr<ui::LayerAnimationElement> animation_element =
       ui::LayerAnimationElement::CreateColorElement(
           SK_ColorRED, base::TimeDelta::FromMilliseconds(100));
   ui::LayerAnimationSequence* animation_sequence =
       new ui::LayerAnimationSequence(std::move(animation_element));
   TestMetricsReporter reporter;
   animation_sequence->SetAnimationMetricsReporter(&reporter);
@@ skipping 12 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