Remove --disable-app-shims.

App shims have been enabled by default for 3 milestones
(since r242711).

BUG=350161

Review URL: https://codereview.chromium.org/298953002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272786 0039d316-1c4b-4281-b951-d872f2087c98
void AppLauncherHandler::PromptToEnableApp(const std::string& extension_id) {
  if (!extension_id_prompting_.empty())
    return;  // Only one prompt at a time.

  extension_id_prompting_ = extension_id;
  extension_enable_flow_.reset(new ExtensionEnableFlow(
      Profile::FromWebUI(web_ui()), extension_id, this));
  extension_enable_flow_->StartForWebContents(web_ui()->GetWebContents());
}

void AppLauncherHandler::PromptToEnableApp(const std::string& extension_id) {
  if (!extension_id_prompting_.empty())
    return;  // Only one prompt at a time.

  extension_id_prompting_ = extension_id;
  extension_enable_flow_.reset(new ExtensionEnableFlow(
      Profile::FromWebUI(web_ui()), extension_id, this));
  extension_enable_flow_->StartForWebContents(web_ui()->GetWebContents());
}
