Merge custom bindings for context menus

De-duplicated the logic for contextMenus custom bindings.
And changed the contextMenus.update method, so that calling it with
"onclick: null" will remove the onclick handler.

BUG=461869
TEST=browser_tests ExtensionContextMenuBrowserTest.UpdateOnclick

Review URL: https://codereview.chromium.org/948243005

Cr-Commit-Position: refs/heads/master@{#323880}

3 files changed, 149 insertions, 102 deletions

diff --git a/extensions/renderer/resources/context_menus_custom_bindings.js b/extensions/renderer/resources/context_menus_custom_bindings.js
index 0e82711b5..fe5cec9 100644
--- a/extensions/renderer/resources/context_menus_custom_bindings.js
+++ b/extensions/renderer/resources/context_menus_custom_bindings.js
@@ -5,117 +5,22 @@
 // Custom binding for the contextMenus API.
 
 var binding = require('binding').Binding.create('contextMenus');
-
-var contextMenuNatives = requireNative('context_menus');
-var sendRequest = require('sendRequest').sendRequest;
-var Event = require('event_bindings').Event;
-var lastError = require('lastError');
+var contextMenusHandlers = require('contextMenusHandlers');
 
 binding.registerCustomHook(function(bindingsAPI) {
   var apiFunctions = bindingsAPI.apiFunctions;
 
-  var contextMenus = {};
-  contextMenus.generatedIdHandlers = {};
-  contextMenus.stringIdHandlers = {};
-  var eventName = 'contextMenus';
-  contextMenus.event = new Event(eventName);
-  contextMenus.getIdFromCreateProperties = function(prop) {
-    if (typeof(prop.id) !== 'undefined')
-      return prop.id;
-    return prop.generatedId;
-  };
-  contextMenus.handlersForId = function(id) {
-    if (typeof(id) === 'number')
-      return contextMenus.generatedIdHandlers;
-    return contextMenus.stringIdHandlers;
-  };
-  contextMenus.ensureListenerSetup = function() {
-    if (contextMenus.listening) {
-      return;
-    }
-    contextMenus.listening = true;
-    contextMenus.event.addListener(function() {
-      // An extension context menu item has been clicked on - fire the onclick
-      // if there is one.
-      var id = arguments[0].menuItemId;
-      var onclick = contextMenus.handlersForId(id)[id];
-      if (onclick) {
-        $Function.apply(onclick, null, arguments);
-      }
-    });
-  };
-
-  apiFunctions.setHandleRequest('create', function() {
-    var args = arguments;
-    var id = contextMenuNatives.GetNextContextMenuId();
-    args[0].generatedId = id;
-    var optArgs = {
-      customCallback: this.customCallback,
-    };
-    sendRequest(this.name, args, this.definition.parameters, optArgs);
-    return contextMenus.getIdFromCreateProperties(args[0]);
-  });
-
-  apiFunctions.setCustomCallback('create',
-      function(name, request, callback, response) {
-    if (lastError.hasError(chrome)) {
-      if (callback)
-        callback();
-      return;
-    }
+  var handlers = contextMenusHandlers.create(false /* isWebview */);
 
-    var id = contextMenus.getIdFromCreateProperties(request.args[0]);
+  apiFunctions.setHandleRequest('create', handlers.requestHandlers.create);
 
-    // Set up the onclick handler if we were passed one in the request.
-    var onclick = request.args.length ? request.args[0].onclick : null;
-    if (onclick) {
-      contextMenus.ensureListenerSetup();
-      contextMenus.handlersForId(id)[id] = onclick;
-    }
-    if (callback)
-      callback();
-  });
+  apiFunctions.setCustomCallback('create', handlers.callbacks.create);
 
-  apiFunctions.setCustomCallback('remove',
-      function(name, request, callback, response) {
-    if (lastError.hasError(chrome)) {
-      if (callback)
-        callback();
-      return;
-    }
-    var id = request.args[0];
-    delete contextMenus.handlersForId(id)[id];
-    if (callback)
-      callback();
-  });
+  apiFunctions.setCustomCallback('remove', handlers.callbacks.remove);
 
-  apiFunctions.setCustomCallback('update',
-      function(name, request, callback, response) {
-    if (lastError.hasError(chrome)) {
-      if (callback)
-        callback();
-      return;
-    }
-    var id = request.args[0];
-    if (request.args[1].onclick) {
-      contextMenus.handlersForId(id)[id] = request.args[1].onclick;
-    }
-    if (callback)
-      callback();
-  });
+  apiFunctions.setCustomCallback('update', handlers.callbacks.update);
 
-  apiFunctions.setCustomCallback('removeAll',
-      function(name, request, callback, response) {
-    if (lastError.hasError(chrome)) {
-      if (callback)
-        callback();
-      return;
-    }
-    contextMenus.generatedIdHandlers = {};
-    contextMenus.stringIdHandlers = {};
-    if (callback)
-      callback();
-  });
+  apiFunctions.setCustomCallback('removeAll', handlers.callbacks.removeAll);
 });
 
 exports.binding = binding.generate();
diff --git a/extensions/renderer/resources/context_menus_handlers.js b/extensions/renderer/resources/context_menus_handlers.js
new file mode 100644
index 0000000..b334900
--- /dev/null
+++ b/extensions/renderer/resources/context_menus_handlers.js
@@ -0,0 +1,141 @@
+// Copyright 2015 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.
+
+// Implementation of custom bindings for the contextMenus API.
+// This is used to implement the contextMenus API for extensions and for the
+// <webview> tag (see chrome_web_view_experimental.js).
+
+var contextMenuNatives = requireNative('context_menus');
+var sendRequest = require('sendRequest').sendRequest;
+var Event = require('event_bindings').Event;
+var lastError = require('lastError');
+
+// Add the bindings to the contextMenus API.
+function createContextMenusHandlers(isWebview) {
+  var eventName = isWebview ? 'webViewInternal.contextMenus' : 'contextMenus';
+  // Some dummy value for chrome.contextMenus instances.
+  // Webviews use positive integers, and 0 to denote an invalid webview ID.
+  // The following constant is -1 to avoid any conflicts between webview IDs and
+  // extensions.
+  var INSTANCEID_NON_WEBVIEW = -1;
+
+  // Generates a customCallback for a given method. |handleCallback| will be
+  // invoked with |request.args| as parameters.
+  function createCustomCallback(handleCallback) {
+    return function(name, request, callback) {
+      if (lastError.hasError(chrome)) {
+        if (callback)
+          callback();
+        return;
+      }
+      var args = request.args;
+      if (!isWebview) {
+        // <webview>s have an extra item in front of the parameter list, which
+        // specifies the viewInstanceId of the webview. This is used to hide
+        // context menu events in one webview from another.
+        // The non-webview chrome.contextMenus API is not called with such an
+        // ID, so we prepend an ID to match the function signature.
+        args = $Array.concat([INSTANCEID_NON_WEBVIEW], args);
+      }
+      $Function.apply(handleCallback, null, args);
+      if (callback)
+        callback();
+    };
+  }
+
+  var contextMenus = {};
+  contextMenus.handlers = {};
+  contextMenus.event = new Event(eventName);
+
+  contextMenus.getIdFromCreateProperties = function(createProperties) {
+    if (typeof createProperties.id !== 'undefined')
+      return createProperties.id;
+    return createProperties.generatedId;
+  };
+
+  contextMenus.handlersForId = function(instanceId, id) {
+    if (!contextMenus.handlers[instanceId]) {
+      contextMenus.handlers[instanceId] = {
+        generated: {},
+        string: {}
+      };
+    }
+    if (typeof id === 'number')
+      return contextMenus.handlers[instanceId].generated;
+    return contextMenus.handlers[instanceId].string;
+  };
+
+  contextMenus.ensureListenerSetup = function() {
+    if (contextMenus.listening) {
+      return;
+    }
+    contextMenus.listening = true;
+    contextMenus.event.addListener(function(info) {
+      var instanceId = INSTANCEID_NON_WEBVIEW;
+      if (isWebview) {
+        instanceId = info.webviewInstanceId;
+        // Don't expose |webviewInstanceId| via the public API.
+        delete info.webviewInstanceId;
+      }
+
+      var id = info.menuItemId;
+      var onclick = contextMenus.handlersForId(instanceId, id)[id];
+      if (onclick) {
+        $Function.apply(onclick, null, arguments);
+      }
+    });
+  };
+
+  // To be used with apiFunctions.setHandleRequest
+  var requestHandlers = {};
+  // To be used with apiFunctions.setCustomCallback
+  var callbacks = {};
+
+  requestHandlers.create = function() {
+    var createProperties = isWebview ? arguments[1] : arguments[0];
+    createProperties.generatedId = contextMenuNatives.GetNextContextMenuId();
+    var optArgs = {
+      customCallback: this.customCallback,
+    };
+    sendRequest(this.name, arguments, this.definition.parameters, optArgs);
+    return contextMenus.getIdFromCreateProperties(createProperties);
+  };
+
+  callbacks.create =
+      createCustomCallback(function(instanceId, createProperties) {
+    var id = contextMenus.getIdFromCreateProperties(createProperties);
+    var onclick = createProperties.onclick;
+    if (onclick) {
+      contextMenus.ensureListenerSetup();
+      contextMenus.handlersForId(instanceId, id)[id] = onclick;
+    }
+  });
+
+  callbacks.remove = createCustomCallback(function(instanceId, id) {
+    delete contextMenus.handlersForId(instanceId, id)[id];
+  });
+
+  callbacks.update =
+      createCustomCallback(function(instanceId, id, updateProperties) {
+    var onclick = updateProperties.onclick;
+    if (onclick) {
+      contextMenus.ensureListenerSetup();
+      contextMenus.handlersForId(instanceId, id)[id] = onclick;
+    } else if (onclick === null) {
+      // When onclick is explicitly set to null, remove the event listener.
+      delete contextMenus.handlersForId(instanceId, id)[id];
+    }
+  });
+
+  callbacks.removeAll = createCustomCallback(function(instanceId) {
+    delete contextMenus.handlers[instanceId];
+  });
+
+  return {
+    requestHandlers: requestHandlers,
+    callbacks: callbacks
+  };
+}
+
+exports.create = createContextMenusHandlers;
diff --git a/extensions/renderer/resources/extensions_renderer_resources.grd b/extensions/renderer/resources/extensions_renderer_resources.grd
index d5c1d67..c9c6299 100644
--- a/extensions/renderer/resources/extensions_renderer_resources.grd
+++ b/extensions/renderer/resources/extensions_renderer_resources.grd
@@ -69,6 +69,7 @@
       <include name="IDR_APP_WINDOW_CUSTOM_BINDINGS_JS" file="app_window_custom_bindings.js" type="BINDATA" />
       <include name="IDR_BINDING_JS" file="binding.js" type="BINDATA" />
       <include name="IDR_CONTEXT_MENUS_CUSTOM_BINDINGS_JS" file="context_menus_custom_bindings.js" type="BINDATA" />
+      <include name="IDR_CONTEXT_MENUS_HANDLERS_JS" file="context_menus_handlers.js" type="BINDATA" />
       <include name="IDR_DECLARATIVE_WEBREQUEST_CUSTOM_BINDINGS_JS" file="declarative_webrequest_custom_bindings.js" type="BINDATA" />
       <include name="IDR_EXTENSION_CUSTOM_BINDINGS_JS" file="extension_custom_bindings.js" type="BINDATA" />
       <include name="IDR_GREASEMONKEY_API_JS" file="greasemonkey_api.js" type="BINDATA" />