Factor out content-handling code from TouchBlockState. (bug 1013432 part 1, r=kats)

--HG--
extra : rebase_source : 12a4f865dda6777c146cfec24184ce45d5d54072
Refactor InputQueue to hold more than touch events. (bug 1013432 part 2, r=kats)

--HG--
extra : rebase_source : cd3691a2bda6aaf315cf3b844e4fdd3aa8b30334
Rename ContentReceivedTouch to ContentReceivedInputBlock. (bug 1013432 part 3, r=kats)

--HG--
extra : rebase_source : ee0d05d4774fac9fb34297953e90e61f1d979d5d
Add wheel events to the APZ input queue. (bug 1013432 part 4, r=kats)

--HG--
extra : rebase_source : beaf39e7ef1eb192e5edd14aa8e55d741f7ffad2
Add scroll listeners to dispatch-to-content regions. (bug 1013432 part 5, r=tn)

--HG--
extra : rebase_source : babd42d9bdae722173821e800bc595fe662ee8f1
Add support for mouse wheel transactions. (bug 1013432 part 6, r=kats)

--HG--
extra : rebase_source : 7230d0bac38e3faf3c7da2ecaf406b2e02f51146
Move APZ handling of wheel events from nsWindow to RenderFrameParent. (bug 1013432 part 7, r=kats)

--HG--
extra : rebase_source : 6ee0db41a21d333deb511a6403f8178b7fe01bb9