[Media Gallery] Added code to support mtp device media file system on Windows.

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 9bc5ccfa1369ad694e9d49e7bc84770e8818a4a0..be015513449ee0cb32db6e4a4f042d85462ae3f5 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1577,6 +1577,12 @@ const char kUseMockKeychain[]               = "use-mock-keychain";
 #endif
 
 #if defined(OS_WIN)
+// Enables media transfer protocol device media support for
+// mediaGalleries extension API.
+// TODO(kmadhusu): Remove this switch after fixing crbug.com/154835.
+const char kEnableMediaTransferProtocolDeviceOperations[] =
+    "enable-media-transfer-protocol-device-operations";
+
 // For the DelegateExecute verb handler to launch Chrome in metro mode on
 // Windows 8 and higher.  Used when relaunching metro Chrome.
 const char kForceImmersive[]                 = "force-immersive";