Enable stencil clipping in mixed sampled render targets

src/gpu/gl/GrGLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLCaps.h"
 
@@ skipping 337 matching lines @@
         glslCaps->fMixedSamplesSupport =
             ctxInfo.hasExtension("GL_NV_framebuffer_mixed_samples") &&
             ctxInfo.hasExtension("GL_NV_sample_mask_override_coverage") &&
             ctxInfo.hasExtension("GL_EXT_raster_multisample");
     }
     // Workaround NVIDIA bug related to glInvalidateFramebuffer and mixed samples.
     if (kNVIDIA_GrGLDriver == ctxInfo.driver() && fShaderCaps->mixedSamplesSupport()) {
         fDiscardRenderTargetSupport = false;
         fInvalidateFBType = kNone_InvalidateFBType;
     }
+    glslCaps->fProgrammableSampleLocationsSupport = ctxInfo.hasExtension("GL_NV_sample_locations");
+
 
     /**************************************************************************
      * GrCaps fields
      **************************************************************************/
 
     this->initFSAASupport(ctxInfo, gli);
     this->initBlendEqationSupport(ctxInfo);
     this->initStencilFormats(ctxInfo);
 
     if (kGL_GrGLStandard == standard) {
@@ skipping 824 matching lines @@
         for (int p = 0; p < kGrSLPrecisionCount; ++p) {
             glslCaps->fFloatPrecisions[kGeometry_GrShaderType][p] = 
                                                glslCaps->fFloatPrecisions[kVertex_GrShaderType][p];
         }
     }
 }