Bug 913717 - Fix placeholder text for hosted apps. r=paul

browser/devtools/app-manager/content/projects.xhtml

@@ -25,7 +25,7 @@
       <div id="new-packaged-project" onclick="UI.addPackaged()">&projects.addPackaged;</div>
       <div id="new-hosted-project">&projects.addHosted;
         <form onsubmit="UI.addHosted(); return false;" id="new-hosted-project-wrapper">
-          <input value="" id="url-input" type="url" pattern="https?://.+" placeholder="&projects.hostedManifestPlaceHolder;" size="50" />
+          <input value="" id="url-input" type="url" pattern="https?://.+" placeholder="&projects.hostedManifestPlaceHolder2;" size="50" />
           <div onclick="UI.addHosted()" id="new-hosted-project-click"></div>
           <input type="submit" hidden="true"></input>
         </form>

browser/locales/en-US/chrome/browser/devtools/app-manager.dtd

@@ -45,5 +45,5 @@
 <!ENTITY projects.startApp "Start">
 <!ENTITY projects.stopApp "Stop">
 <!ENTITY projects.debugApp "Debug">
-<!ENTITY projects.hostedManifestPlaceHolder "http://example.com/app/webapp.manifest">
+<!ENTITY projects.hostedManifestPlaceHolder2 "http://example.com/app/manifest.webapp">
 <!ENTITY projects.noProject "No project linked. Add a new packaged app below (a directory) or a hosted app (link to a manifest file).">