Start cleaning up 64bit Win warnings

https://codereview.chromium.org/27192003/



git-svn-id: http://skia.googlecode.com/svn/trunk@11764 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index fc3014e..c33dcb7 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -362,7 +362,7 @@
             maxValidVertex = geoSrc.fVertexCount;
             break;
         case kBuffer_GeometrySrcType:
-            maxValidVertex = geoSrc.fVertexBuffer->sizeInBytes() / geoSrc.fVertexSize;
+            maxValidVertex = static_cast<int>(geoSrc.fVertexBuffer->sizeInBytes() / geoSrc.fVertexSize);
             break;
     }
     if (maxVertex > maxValidVertex) {
@@ -379,7 +379,7 @@
                 maxValidIndex = geoSrc.fIndexCount;
                 break;
             case kBuffer_GeometrySrcType:
-                maxValidIndex = geoSrc.fIndexBuffer->sizeInBytes() / sizeof(uint16_t);
+                maxValidIndex = static_cast<int>(geoSrc.fIndexBuffer->sizeInBytes() / sizeof(uint16_t));
                 break;
         }
         if (maxIndex > maxValidIndex) {