Remove active fetcher count.

Originally the code assumed that there would be an equal number of requests
for bitmap fetches and replies.  However, in some cases, we get more replies.
Often a single request for a bitmap means that we get multiple replies for
different sizes.

I had previously fixed this by bypassing the active_fetcher_count to see when
we were done by instead checking for the bitmaps we asked for.  However, I did
not remove the now unused active_fetcher_count.

This change totally removes the variable, and always checks that we have the
bitmaps both in the "nothing to fetch" case and the "everything fetched" case.

BUG=277686

Review URL: https://codereview.chromium.org/101503006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244906 0039d316-1c4b-4281-b951-d872f2087c98
Do not dispatch install related API events for ephemeral apps

- Do not dispatch the chrome.runtime.onInstalled() event.
- Do not navigate to the URL set by chrome.runtime.setUninstallUrl()
  when the app is removed.

BUG=312460

Review URL: https://codereview.chromium.org/111723011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244907 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244907