Allow extension extensions to be case-insensitive.

chrome/common/extensions/extension.cc

Index: chrome/common/extensions/extension.cc
===================================================================
--- chrome/common/extensions/extension.cc	(revision 19502)
+++ chrome/common/extensions/extension.cc	(working copy)
@@ -12,6 +12,7 @@
 #include "base/string_util.h"
 #include "base/third_party/nss/blapi.h"
 #include "base/third_party/nss/sha256.h"
+#include "chrome/common/chrome_constants.h"
 #include "chrome/common/extensions/extension_error_reporter.h"
 #include "chrome/common/extensions/extension_error_utils.h"
 #include "chrome/common/extensions/user_script.h"
@@ -199,6 +200,13 @@
 }
 
 // static
+bool Extension::IsExtension(const FilePath& file_name) {
+  return file_name.MatchesExtension(
+      FilePath::StringType(FILE_PATH_LITERAL(".")) +
+      chrome::kExtensionFileExtension);
+}
+
+// static
 bool Extension::IdIsValid(const std::string& id) {
   // Verify that the id is legal.
   if (id.size() != (kIdSize * 2))