app_list: Initial version of the start page.

- Add a StartPageService PKS that holds the start page contents and
  app recommendation generator;
- Implement the initial app recommendation using the 4 most recent apps;
- Expose the start page contents in AppListViewDelegate;
- Update AppsGridView could to handle start page case;
- Implement a WebUI for the start page contents;
- Put the start page feature behind a flag;
- Add a switch to override the start page url for easier mocking;

BUG=268660,268661

Review URL: https://codereview.chromium.org/25152002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226940 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 5 insertions, 0 deletions

diff --git a/ui/app_list/test/app_list_test_view_delegate.cc b/ui/app_list/test/app_list_test_view_delegate.cc
index 1a56714..493fb56 100644
--- a/ui/app_list/test/app_list_test_view_delegate.cc
+++ b/ui/app_list/test/app_list_test_view_delegate.cc
@@ -44,5 +44,9 @@ gfx::ImageSkia AppListTestViewDelegate::GetWindowIcon() {
   return gfx::ImageSkia();
 }
 
+content::WebContents* AppListTestViewDelegate::GetStartPageContents() {
+  return NULL;
+}
+
 }  // namespace test
 }  // namespace app_list
diff --git a/ui/app_list/test/app_list_test_view_delegate.h b/ui/app_list/test/app_list_test_view_delegate.h
index 344c318..f70d764 100644
--- a/ui/app_list/test/app_list_test_view_delegate.h
+++ b/ui/app_list/test/app_list_test_view_delegate.h
@@ -49,6 +49,7 @@ class AppListTestViewDelegate  : public AppListViewDelegate {
   virtual void OpenFeedback() OVERRIDE {}
   virtual void ShowForProfileByPath(
       const base::FilePath& profile_path) OVERRIDE {};
+  virtual content::WebContents* GetStartPageContents() OVERRIDE;
 
  private:
   int activate_count_;