b=951799, cache uniforms in OGLShaderProgram, part 1; r=bjacob
b=951799, cache uniforms in OGLShaderProgram, part 2 - fix LayerProgramProjectionMatrix; r=bjacob
b=951799, cache uniforms in OGLShaderProgram, part 3 - inline; r=bjacob
b=738872, implement WebGL OES_texture_half_float; part 1 - GLContext; r=jgilbert
b=738872, implement WebGL OES_texture_half_float; part 2 - core impl; r=jgilbert
b=738872; implement WebGL OES_texture_half_float; part 3 - desktop GL compat; r=jgilbert