Change manifest handler interface to always (implicitly) pass the entire manifest to handlers.

chrome/common/extensions/manifest_handler.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_COMMON_EXTENSIONS_MANIFEST_HANDLER_H_
 #define CHROME_COMMON_EXTENSIONS_MANIFEST_HANDLER_H_
 
+#include <set>
 #include <string>
-#include <vector>
 
 #include "base/string16.h"
-
-namespace base {
-class Value;
-}
+#include "chrome/common/extensions/extension.h"
 
 namespace extensions {
 
-class Extension;
+class Manifest;
 
 class ManifestHandler {
  public:
   ManifestHandler();
   virtual ~ManifestHandler();
 
-  // Attempts to parse the manifest value.
+  // Attempts to parse the extension's manifest.
   // Returns true on success or false on failure; if false, |error| will
   // be set to a failure message.
-  virtual bool Parse(const base::Value* value,
-                     Extension* extension,
-                     string16* error) = 0;
+  virtual bool Parse(Extension* extension, string16* error) = 0;
 
-  // Perform any initialization which is necessary when the Handler's key is
-  // not present in the manifest.
-  // Returns true on success or false on failure; if false, |error| will
-  // be set to a failure message.
-  virtual bool HasNoKey(Extension* extension, string16* error);
+  // If false (the default), only parse the manifest if a registered
+  // key is present in the manifest. If true, always attempt to parse
+  // the manifest for this extension type, even if no registered keys
+  // are present.

[Matt Perry, 2013/01/29 00:58:47]

Could you add a sentence or two on when this would be useful? I didn't
understand until I dug through and looked at examples.

[Yoyo Zhou, 2013/01/29 04:32:42]

Done.

+  virtual bool AlwaysParseForType(Extension::Type type);
 
-  // Associate |handler| with |key| in the manifest. Takes ownership
-  // of |handler|. TODO(yoz): Decide how to handle dotted subkeys.
+  // Associate |handler| with |key| in the manifest. A handler can register
+  // for multiple keys. The global registry takes ownership of |handler|;
+  // if it has an existing handler for |key|, it replaces it with this one.
+  //
   // WARNING: Manifest handlers registered only in the browser process
-  // are not available to renderers.
+  // are not available to renderers or utility processes.
   static void Register(const std::string& key, ManifestHandler* handler);
 
-  // Get the manifest handler associated with |key|, or NULL
-  // if there is none.
-  static ManifestHandler* Get(const std::string& key);
-
-  // If the handler is not handling most of the keys, it may be
-  // more efficient to have a list of keys to iterate over.
-  // TODO(yoz): this isn't the long-term solution.
-  static std::vector<std::string> GetKeys();
+  // Get all registered manifest handlers that should parse |manifest|.
+  static std::set<ManifestHandler*> GetHandlers(const Manifest* manifest);
 };
 
-
 }  // namespace extensions
 
 #endif  // CHROME_COMMON_EXTENSIONS_MANIFEST_HANDLER_H_