This CL makes the GrTextContext be owned (and hidden) by the GrDrawContext. This funnels all the drawText* calls through the GrDrawContext and hides the (dispreferred) GrPipelineBuilder drawText variant.
Some consequences of this are:
GrDrawContext now has to get the text drawing settings (i.e., SkDeviceProperties & useDFT). This means that we need a separate GrDrawContext for each combination of pixel geometry and DFT-use.
All the GrTextContext-derived classes now get a back pointer to the originating GrDrawContext so their method calls no longer take one.
Review URL: https://codereview.chromium.org/1175553002
This is mainly a mechanical CL. There were some fiddly bits in GrContext.cpp where it no longer had access to the GrDrawTarget (and had to use the new GrDrawContext).
I've converted GrAARectRenderer & GrOvalRenderer into static classes so I could stop allocating them.
Review URL: https://codereview.chromium.org/1151283004
