Simple http fallback for the data reduction proxy.

This CL adds a new command line option and preprocessor macro for a second proxy that the data reduction proxy feature will add to its configs as a fallback from the primary proxy. If the fallback proxy isn't defined, only the primary proxy is part of the configurations, and vice-versa. 

(Also fixes a bug where a http proxy specified on the command line would still be configured as HTTPS in the generated PAC file). 

BUG=306634

Review URL: https://codereview.chromium.org/30883003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230728 0039d316-1c4b-4281-b951-d872f2087c98
Remove BrowserPluginGuestHelper since it's not needed. BrowserPluginGuest already swallowed the IPCs that it dispatched. For the two that weren't dispatched but were swallowed by BrowserPluginGuestHelper, we can use empty IPC_MESSAGE_HANDLER_GENERIC statements. This also removes duplication of the list of handled IPCs.

This is part of the work in removing RenderViewHostObserver.

BUG=306569
R=fsamuel@chromium.org

Review URL: https://codereview.chromium.org/35853003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230729 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230729
android: Run upload results script from the parent of src/

Matches other ports.

BUG=310981
TBR=dpranke

Review URL: https://codereview.chromium.org/40253002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230730 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230730