Move DisplayCompositor code to new component.

components/frame_sinks/frame_sinks_export.h

Index: components/frame_sinks/frame_sinks_export.h
diff --git a/components/frame_sinks/frame_sinks_export.h b/components/frame_sinks/frame_sinks_export.h
new file mode 100644
index 0000000000000000000000000000000000000000..1f8af62ebd81de43439cff156624ceef712b1867
--- /dev/null
+++ b/components/frame_sinks/frame_sinks_export.h
@@ -0,0 +1,34 @@
+// 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 COMPONENTS_FRAME_SINKS_FRAME_SINKS_EXPORT_H_
+#define COMPONENTS_FRAME_SINKS_FRAME_SINKS_EXPORT_H_
+
+#if defined(COMPONENT_BUILD)
+
+#if defined(WIN32)
+
+#if defined(FRAME_SINKS_IMPLEMENTATION)
+#define FRAME_SINKS_EXPORT __declspec(dllexport)
+#else
+#define FRAME_SINKS_EXPORT __declspec(dllimport)
+#endif
+
+#else  // !defined(WIN32)
+
+#if defined(FRAME_SINKS_IMPLEMENTATION)
+#define FRAME_SINKS_EXPORT __attribute__((visibility("default")))
+#else
+#define FRAME_SINKS_EXPORT
+#endif
+
+#endif
+
+#else  // !defined(COMPONENT_BUILD)
+
+#define FRAME_SINKS_EXPORT
+
+#endif
+
+#endif  // COMPONENTS_FRAME_SINKS_FRAME_SINKS_EXPORT_H_