Move ContentDecryptionModule* to platform/

Source/platform/PlatformExport.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 32 matching lines @@
 #else
 #define PLATFORM_EXPORT __declspec(dllimport)
 #endif
 #else // defined(WIN32)
 #define PLATFORM_EXPORT __attribute__((visibility("default")))
 #endif
 #else // defined(COMPONENT_BUILD)
 #define PLATFORM_EXPORT
 #endif
 
+#if defined(_MSC_VER)
+// MSVC Compiler warning C4275:
+// non dll-interface class 'Bar' used as base for dll-interface class 'Foo'.
+// Note that this is intended to be used only when no access to the base class'
+// static data is done through derived classes or inline methods. For more info,
+// see http://msdn.microsoft.com/en-us/library/3tdb471s(VS.80).aspx
+//
+// This pragma will allow exporting a class that inherits from a non-exported
+// base class, anywhere in the Blink platform component. This is only
+// a problem when using the MSVC compiler on Windows.
+#pragma warning(suppress:4275)
+#endif
+
 #endif // PlatformExport_h