Differentiate maxColorSamples and maxStencilSamples in GrCaps

src/gpu/gl/GrGLGpu.cpp

Index: src/gpu/gl/GrGLGpu.cpp
diff --git a/src/gpu/gl/GrGLGpu.cpp b/src/gpu/gl/GrGLGpu.cpp
index 248a5dfbd250e91f45daa974be4f8b8d929324bc..d3fe62f91519b3e4aa99719404a19d0e0bf3d610 100644
--- a/src/gpu/gl/GrGLGpu.cpp
+++ b/src/gpu/gl/GrGLGpu.cpp
@@ -483,7 +483,11 @@ GrTexture* GrGLGpu::onWrapBackendTexture(const GrBackendTextureDesc& desc,
     surfDesc.fWidth = desc.fWidth;
     surfDesc.fHeight = desc.fHeight;
     surfDesc.fConfig = desc.fConfig;
-    surfDesc.fSampleCnt = SkTMin(desc.fSampleCnt, this->caps()->maxSampleCount());
+    // We require the sample count to be less than both the max color sample count and
+    // max stencil sample count supported by the system
+    int maxSampleCount = SkTMin(this->caps()->maxColorSampleCount(),
+                                this->caps()->maxStencilSampleCount());
+    surfDesc.fSampleCnt = SkTMin(desc.fSampleCnt, maxSampleCount);

[bsalomon, 2016/01/15 18:08:29]

Probably want to consider mixed samples here

     // FIXME:  this should be calling resolve_origin(), but Chrome code is currently
     // assuming the old behaviour, which is that backend textures are always
     // BottomLeft, even for non-RT's.  Once Chrome is fixed, change this to:
@@ -533,7 +537,11 @@ GrRenderTarget* GrGLGpu::onWrapBackendRenderTarget(const GrBackendRenderTargetDe
     desc.fFlags = kCheckAllocation_GrSurfaceFlag | kRenderTarget_GrSurfaceFlag;
     desc.fWidth = wrapDesc.fWidth;
     desc.fHeight = wrapDesc.fHeight;
-    desc.fSampleCnt = SkTMin(wrapDesc.fSampleCnt, this->caps()->maxSampleCount());
+    // We require the sample count to be less than both the max color sample count and
+    // max stencil sample count supported by the system
+    int maxSampleCount = SkTMin(this->caps()->maxColorSampleCount(),
+                                this->caps()->maxStencilSampleCount());
+    desc.fSampleCnt = SkTMin(wrapDesc.fSampleCnt, maxSampleCount);

[bsalomon, 2016/01/15 18:08:29]

and here

     desc.fOrigin = resolve_origin(wrapDesc.fOrigin, true);
 
     return GrGLRenderTarget::CreateWrapped(this, desc, idDesc, wrapDesc.fStencilBits);