Fix progress event not firing when load has completed.
Fix progress event not firing when load has completed.

When media has fully loaded, make sure we transition through
the 'loaded' network state, otherwise the progress event on
final load won't be fired.

There probably should be a layout test for this. Will raise an issue.

BUG=59372
TEST=local handcrafted repro, media layout tests.

Review URL: http://codereview.chromium.org/6581012

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@75985 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser