added support for glMinSampleShading

src/views/mac/SkNSView.mm

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #import "SkNSView.h"
 #include "SkCanvas.h"
 #include "SkSurface.h"
@@ skipping 319 matching lines @@
 #include <OpenGL/OpenGL.h>
 
 static CGLContextObj createGLContext(int msaaSampleCount) {
     GLint major, minor;
     CGLGetVersion(&major, &minor);
     
     static const CGLPixelFormatAttribute attributes[] = {
         kCGLPFAStencilSize, (CGLPixelFormatAttribute) 8,
         kCGLPFAAccelerated,
         kCGLPFADoubleBuffer,
+        kCGLPFAOpenGLProfile, (CGLPixelFormatAttribute) kCGLOGLPVersion_3_2_Core,
         (CGLPixelFormatAttribute)0
     };
     
     CGLPixelFormatObj format;
     GLint npix = 0;
     if (msaaSampleCount > 0) {
         static int kAttributeCount = SK_ARRAY_COUNT(attributes);
         CGLPixelFormatAttribute msaaAttributes[kAttributeCount + 5];
         memcpy(msaaAttributes, attributes, sizeof(attributes));
         SkASSERT(0 == msaaAttributes[kAttributeCount - 1]);
@@ skipping 70 matching lines @@
 }
 
 - (void)setVSync:(bool)enable {
     if (fGLContext) {
         GLint interval = enable ? 1 : 0;
         CGLContextObj ctx = (CGLContextObj)[fGLContext CGLContextObj];
         CGLSetParameter(ctx, kCGLCPSwapInterval, &interval);
     }
 }
 @end