Rename internal gfx::Image members to be less confusing with Cocoa types.

ui/base/resource/resource_bundle_mac.mm

Index: ui/base/resource/resource_bundle_mac.mm
diff --git a/ui/base/resource/resource_bundle_mac.mm b/ui/base/resource/resource_bundle_mac.mm
index 0508177e090a0d7bddc14ff5b9bf36d8a016fb69..2c66d6088b7ce350974ddf09f4515c9c5f563971 100644
--- a/ui/base/resource/resource_bundle_mac.mm
+++ b/ui/base/resource/resource_bundle_mac.mm
@@ -71,7 +71,7 @@ gfx::Image& ResourceBundle::GetNativeImageNamed(int resource_id) {
     base::AutoLock lock(*lock_);
     ImageMap::const_iterator found = images_.find(resource_id);
     if (found != images_.end()) {
-      if (!found->second->HasRepresentation(gfx::Image::kNSImageRep)) {
+      if (!found->second->HasRepresentation(gfx::Image::kImageRepCocoa)) {
         DLOG(WARNING) << "ResourceBundle::GetNativeImageNamed() is returning a"
           << " cached gfx::Image that isn't backed by an NSImage. The image"
           << " will be converted, rather than going through the NSImage loader."