Make pull to refresh not perform regular reload (with cache revalidation)
Pull-to-refresh action on Android is currently handled as a
regular reload, which causes revalidation of cached contents,
however the action would usually imply that the user wants to
refresh the 'contents' rather than reloading everything (e.g.
to reset the page contents when something's screwed up).
This change adds new a reload method, i.e. reloadToRefreshContent,
to the navigation controller so that we can distinguish the two
reload cases.
The new behavior (i.e. non-validating reload on pull-to-refresh)
will be only enabled if the following command-line flag is given:
"--enable-non-validating-reload-on-refresh-content"
(I plan to add chrome://flags once I can land this)
BUG=558829
Review URL: https://codereview.chromium.org/1493403002
Cr-Commit-Position: refs/heads/master@{#365413}
11 files changed
