Workaround for Intel 6xxx clear to 0/1 bug

ui/gl/gl_workarounds.h

Index: ui/gl/gl_workarounds.h
diff --git a/ui/gl/gl_workarounds.h b/ui/gl/gl_workarounds.h
new file mode 100644
index 0000000000000000000000000000000000000000..2b93214209af78cd6a38392dec8f1e5eef4cc3b6
--- /dev/null
+++ b/ui/gl/gl_workarounds.h
@@ -0,0 +1,18 @@
+// Copyright 2017 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.
+
+#ifndef UI_GL_GL_WORKAROUNDS_H_
+#define UI_GL_GL_WORKAROUNDS_H_
+
+namespace gl {
+
+struct GLWorkarounds {
+  // glClearColor does not always work on Intel 6xxx Mac drivers. See
+  // crbug.com/710443.
+  bool clear_to_zero_or_one_broken = false;
+};
+
+}  // namespace gl
+
+#endif  // UI_GL_GL_WORKAROUNDS_H_