Add IsTsfAwareRequired method

base/win/metro.cc

Index: base/win/metro.cc
diff --git a/base/win/metro.cc b/base/win/metro.cc
index a8436cbf6ceabab4d93d95992ce3efa07144d4b5..598217eb5e840c6d1bfe02c20d8f6e6375e460dd 100644
--- a/base/win/metro.cc
+++ b/base/win/metro.cc
@@ -73,6 +73,12 @@ bool IsMetroProcess() {
   return state == kImmersiveTrue;
 }
 
+bool IsTsfAwareRequired() {
+  // Although this function is equal to IsMetroProcess at this moment,
+  // Chrome for Win7 and Vista may support TSF in the future.
+  return IsMetroProcess();
+}
+
 wchar_t* LocalAllocAndCopyString(const string16& src) {
   size_t dest_size = (src.length() + 1) * sizeof(wchar_t);
   wchar_t* dest = reinterpret_cast<wchar_t*>(LocalAlloc(LPTR, dest_size));