First pass at cleaning up html lib warnings from the analyzer.

tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate

Index: tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate b/tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate
index d04c3bbb06eaec56082507afbf4fc262a2682350..bec16f9aa7e7b604c9bd267c5ec7c9e8e21d5dad 100644
--- a/tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate
+++ b/tools/dom/templates/html/impl/impl_WebGLRenderingContext.darttemplate
@@ -67,11 +67,11 @@ $endif
 $if DART2JS
   @JSName('texSubImage2D')
   void texSubImage2DUntyped(int targetTexture, int levelOfDetail,
-      int internalFormat, int format, int type, data) native;
+      int xOffset, int yOffset, int format, int type, data) native;
 $else
   void texSubImage2DUntyped(int targetTexture, int levelOfDetail, 
-      int internalFormat, int format, int type, data) {
-    texSubImage2D(targetTexture, levelOfDetail, internalFormat,
+      int xOffset, int yOffset, int format, int type, data) {
+    texSubImage2D(targetTexture, levelOfDetail, xOffset, yOffset,
         format, type, data);
   }
 $endif
@@ -82,14 +82,14 @@ $endif
 $if DART2JS
   @JSName('texSubImage2D')
   void texSubImage2DTyped(int targetTexture, int levelOfDetail,
-      int internalFormat, int width, int height, int border, int format,
+      int xOffset, int yOffset, int width, int height, int border, int format,
       int type, TypedData data) native;
 $else
   void texSubImage2DTyped(int targetTexture, int levelOfDetail,
-      int internalFormat, int width, int height, int border, int format,
+      int xOffset, int yOffset, int width, int height, int format,
       int type, TypedData data) {
-    texSubImage2D(targetTexture, levelOfDetail, internalFormat,
-        width, height, border, format, type, data);
+    texSubImage2D(targetTexture, levelOfDetail, xOffset, yOffset,
+        width, height, format, type, data);
   }
 $endif
 }