Fix and enable warning C4244 (Conversion from 'type1' to 'type2', possible loss of data)

Change-Id: Id0e06d7d6600344d858f00dabc219d79289bbc82
Reviewed-on: https://chromium-review.googlesource.com/265020
Tested-by: Minmin Gong <mgong@microsoft.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/renderer/gl/VertexArrayGL.cpp b/src/libANGLE/renderer/gl/VertexArrayGL.cpp
index 996321d..76635a0 100644
--- a/src/libANGLE/renderer/gl/VertexArrayGL.cpp
+++ b/src/libANGLE/renderer/gl/VertexArrayGL.cpp
@@ -264,7 +264,7 @@
             // Find the index range in the buffer
             const IndexRangeCache *rangeCache = mElementArrayBuffer.get()->getIndexRangeCache();
 
-            if (!rangeCache->findRange(type, elementArrayBufferOffset, count, outIndexRange))
+            if (!rangeCache->findRange(type, static_cast<unsigned int>(elementArrayBufferOffset), count, outIndexRange))
             {
                 // Need to compute the index range.
                 mStateManager->bindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementArrayBufferID);
@@ -273,7 +273,7 @@
                 *outIndexRange = IndexRangeCache::ComputeRange(type, elementArrayBufferPointer + elementArrayBufferOffset, count);
 
                 // TODO: Store the range cache at the impl level since the gl::Buffer object is supposed to remain constant
-                const_cast<IndexRangeCache*>(rangeCache)->addRange(type, elementArrayBufferOffset, count, *outIndexRange);
+                const_cast<IndexRangeCache*>(rangeCache)->addRange(type, static_cast<unsigned int>(elementArrayBufferOffset), count, *outIndexRange);
 
                 if (!mFunctions->unmapBuffer(GL_ELEMENT_ARRAY_BUFFER))
                 {