Move Extension Location and Type enums to Manifest, and move InstallWarning to its own file.

chrome/common/extensions/extension_set_unittest.cc

Index: chrome/common/extensions/extension_set_unittest.cc
diff --git a/chrome/common/extensions/extension_set_unittest.cc b/chrome/common/extensions/extension_set_unittest.cc
index 0bc8e92c8020f90e36a9fdf633eef18a902d88f8..ba2649bb997e36bdfdedfac0586ce8c17180e3ec 100644
--- a/chrome/common/extensions/extension_set_unittest.cc
+++ b/chrome/common/extensions/extension_set_unittest.cc
@@ -40,7 +40,7 @@ scoped_refptr<Extension> CreateTestExtension(const std::string& name,
 
   std::string error;
   scoped_refptr<Extension> extension(
-      Extension::Create(path, Extension::INTERNAL, manifest,
+      Extension::Create(path, extensions::Manifest::INTERNAL, manifest,
                         Extension::NO_FLAGS, &error));
   EXPECT_TRUE(extension.get()) << error;
   return extension;