Bug 912090 - Switch to a tag while CAF deals with crazy bots

Change-Id: I62ea7177fcfb17ffb3608c7c143d7c484c2e1ded
Bug 910134: Switch nexus-4 manifest to pull from CAF instead of AOSP.  r=mwu
Switch back to b2g/ics_strawberry branch

Change-Id: I0e88af707f0fce0d2071d25c142aab21618cdcf8
Point libpng and frameworks/av to our forks

This is necessary for:

frameworks/av : https://bugzilla.mozilla.org/show_bug.cgi?id=911548 

libpng : https://bugzilla.mozilla.org/show_bug.cgi?id=915201
Change Helix on master to use Gaia & Gecko on master not v1.1.0hd branch.