Move convolution from code in GrGLProgram to new GrConvolutionEffect
class. This is the first test of the new Ganesh shader pipeline.

Also includes some cleanup of the gpu.gyp file: added src/gpu, allowing
us to remove ../ from many #include directives.

http://codereview.appspot.com/6199053/



git-svn-id: http://skia.googlecode.com/svn/trunk@3887 2bbb7eff-a529-9590-31e7-b0007b416f81
38 files changed