fix warning from scalar --> int32 conversion

BUG=

Review URL: https://codereview.appspot.com/7065050

git-svn-id: http://skia.googlecode.com/svn/trunk@7061 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index 976448d..a67be1c 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -93,6 +93,7 @@
 };
 GR_STATIC_ASSERT(GrDrawState::kMaxTexCoords == GR_ARRAY_COUNT(gTexCoordMasks));
 
+#ifdef SK_DEBUG
 bool check_layout(GrVertexLayout layout) {
     // can only have 1 or 0 bits set for each stage.
     for (int s = 0; s < GrDrawState::kNumStages; ++s) {
@@ -103,6 +104,7 @@
     }
     return true;
 }
+#endif
 
 int num_tex_coords(GrVertexLayout layout) {
     int cnt = 0;
@@ -467,7 +469,7 @@
 
 GrDrawTarget::~GrDrawTarget() {
     GrAssert(1 == fGeoSrcStateStack.count());
-    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
+    SkDEBUGCODE(GeometrySrcState& geoSrc = fGeoSrcStateStack.back());
     GrAssert(kNone_GeometrySrcType == geoSrc.fIndexSrc);
     GrAssert(kNone_GeometrySrcType == geoSrc.fVertexSrc);
     fDrawState->unref();