Make application shortcuts point to app_host.exe, install App Host during app installation.

Platform apps need app_host.exe.  2 parts to this change are:
(A) App shortcut now call "app_host.exe" instead of "chrome.exe".
(B) On platform app install, check the presence of app_host.exe.  If it's absent, call quick-enable-application-host to install app_host.exe.  Wait for completion, then proceeding to install app.

(B) should be executed in the FILE thread.  However, some installation tasks may need to wait until quick-enable-application-host finishes (had CRX and unpacked app install in mind, but that's no longer the case).  To avoid blocking the UI thread, we:
- Create AppHostInstaller class, implementing EnsureAppHostInstalled().
- When (in AppShortcutManager::Observe) we want to ensure App Host is installed, we call the routine and specify a callback runction that takes a bool |success| flag.
- AppHostInstaller handles the complexities of switching threads, checking presence of app_host.exe, grabs quick-enable-application-host command, calling it, listening to completion, and then notifies the caller via the callback.

BUG=138319
TEST=install, then install an app. Verify App Host installed. Right-click on an app in NTP, create shortcut. Verify shortcut points to app_host.exe
TBR=brettw

Review URL: https://chromiumcodereview.appspot.com/11054006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@166640 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 5 deletions

diff --git a/chrome/browser/web_applications/web_app_win.cc b/chrome/browser/web_applications/web_app_win.cc
index f1df116..352f921 100644
--- a/chrome/browser/web_applications/web_app_win.cc
+++ b/chrome/browser/web_applications/web_app_win.cc
@@ -16,6 +16,7 @@
 #include "base/win/shortcut.h"
 #include "base/win/windows_version.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/installer/launcher_support/chrome_launcher_support.h"
 #include "content/public/browser/browser_thread.h"
 #include "ui/gfx/icon_util.h"
 
@@ -224,12 +225,12 @@ bool CreatePlatformShortcuts(
     return false;
   }
 
-  FilePath chrome_exe;
-  if (!PathService::Get(base::FILE_EXE, &chrome_exe))
+  FilePath app_host_exe(chrome_launcher_support::GetAnyAppHostPath());
+  if (app_host_exe.empty())
     return false;
 
   // Working directory.
-  FilePath chrome_folder(chrome_exe.DirName());
+  FilePath working_dir(app_host_exe.DirName());
 
   CommandLine cmd_line(CommandLine::NO_PROGRAM);
   cmd_line = ShellIntegration::CommandLineArgsForLauncher(shortcut_info.url,
@@ -268,8 +269,8 @@ bool CreatePlatformShortcuts(
     }
 
     base::win::ShortcutProperties shortcut_properties;
-    shortcut_properties.set_target(chrome_exe);
-    shortcut_properties.set_working_dir(chrome_folder);
+    shortcut_properties.set_target(app_host_exe);
+    shortcut_properties.set_working_dir(working_dir);
     shortcut_properties.set_arguments(wide_switches);
     shortcut_properties.set_description(description);
     shortcut_properties.set_icon(icon_file, 0);