optimize clip for GL msaa render targe that has stencil bits
bug fix for check shader is a bitmap

If shader is bitmap and paint has MaskFilter, do not batch draw, because
it will mess up the transformation matrix
create MSAA render target for blur mask texture
add isRRect in SkPath

SkCanvas::drawPath() can be routed to GrOvalRenderer which is faster
route SkGpuDevice::drawPath() to SkGpuDevice::drawRRect()

if path contains only one RRect, we can route drawPath to drawRRect
which is much faster
fix texture red support in mesa gles driver.

Mesa GLES 3.0 does not support GL_EXT_texture_rg
detect mesa opengl es
rename shaderIsBitmap() to canOptimizeForBitmapShader()
bug fix in canDrawRect

if width <= 0 and paint style == stroke, return false
limit color components to be <= 0xFF
fix bug in worst case point count in GrHairLinePathRenderer
do not use GrOvalRenderer if paint has MaskFilter or has path effect