Make max number of vertex attributes be checked dynamically

src/gpu/GrGeometryProcessor.h

Index: src/gpu/GrGeometryProcessor.h
diff --git a/src/gpu/GrGeometryProcessor.h b/src/gpu/GrGeometryProcessor.h
index 50d0bd51f8b077150f337bd0ea56c5399b52902c..05afd5329a20dd9694b44dea6d83db3009f07c5e 100644
--- a/src/gpu/GrGeometryProcessor.h
+++ b/src/gpu/GrGeometryProcessor.h
@@ -44,10 +44,9 @@ protected:
      * GrGeometryProcessor.
      */
     const Attribute& addVertexAttrib(const Attribute& attribute) {
-        SkASSERT(fNumAttribs < kMaxVertexAttribs);
         fVertexStride += attribute.fOffset;
-        fAttribs[fNumAttribs] = attribute;
-        return fAttribs[fNumAttribs++];
+        fAttribs.push_back(attribute);
+        return fAttribs.back();
     }
 
     void setWillUseGeoShader() { fWillUseGeoShader = true; }