DevTools: Add a shortcut for switching between files with the same name and different extensions.

Source/devtools/front_end/sources/module.json

 {
     "extensions": [
         {
             "type": "@WebInspector.Panel",
             "name": "sources",
             "title": "Sources",
             "order": 2,
             "className": "WebInspector.SourcesPanel"
         },
         {
@@ skipping 73 matching lines @@
                     "platform": "mac",
                     "shortcut": "Meta+O Meta+P"
                 },
                 {
                     "platform": "windows,linux",
                     "shortcut": "Ctrl+O Ctrl+P"
                 }
             ]
         },
         {
+            "type": "@WebInspector.ActionDelegate",
+            "actionId": "sources.switch-file",
+            "className": "WebInspector.SourcesView.SwitchFileActionDelegate",
+            "contextTypes": ["WebInspector.SourcesView"],
+            "bindings": [
+                {
+                    "shortcut": "Alt+O"
+                }
+            ]
+        },
+        {
             "type": "ui-setting",
             "settingName": "javaScriptDisabled",
             "settingType": "custom",
             "className": "WebInspector.SourcesPanel.DisableJavaScriptSettingDelegate"
         },
         {
             "type": "ui-setting",
             "section": "Sources",
             "title": "Search in content scripts",
             "settingName": "searchInContentScripts",
@@ skipping 45 matching lines @@
             "type": "ui-setting",
             "title": "Auto-reload generated CSS",
             "parentSettingName": "cssSourceMapsEnabled",
             "settingName": "cssReloadEnabled",
             "settingType": "checkbox"
         }
     ],
     "dependencies": [ "source_frame" ],
     "scripts": [ "SourcesPanel.js" ]
 }