Fix signed/unsigned warnings in debug build in flushStencil()



git-svn-id: http://skia.googlecode.com/svn/trunk@1028 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/src/GrGpuGL.cpp b/gpu/src/GrGpuGL.cpp
index bb71255..41cb32a 100644
--- a/gpu/src/GrGpuGL.cpp
+++ b/gpu/src/GrGpuGL.cpp
@@ -1464,13 +1464,13 @@
                 frontWriteMask &= userStencilMask;
             }
             GrAssert(settings->fFrontFailOp >= 0 &&
-                     settings->fFrontFailOp < GR_ARRAY_COUNT(grToGLStencilOp));
+                     (unsigned) settings->fFrontFailOp < GR_ARRAY_COUNT(grToGLStencilOp));
             GrAssert(settings->fFrontPassOp >= 0 &&
-                     settings->fFrontPassOp < GR_ARRAY_COUNT(grToGLStencilOp));
+                     (unsigned) settings->fFrontPassOp < GR_ARRAY_COUNT(grToGLStencilOp));
             GrAssert(settings->fBackFailOp >= 0 &&
-                     settings->fBackFailOp < GR_ARRAY_COUNT(grToGLStencilOp));
+                     (unsigned) settings->fBackFailOp < GR_ARRAY_COUNT(grToGLStencilOp));
             GrAssert(settings->fBackPassOp >= 0 &&
-                     settings->fBackPassOp < GR_ARRAY_COUNT(grToGLStencilOp));
+                     (unsigned) settings->fBackPassOp < GR_ARRAY_COUNT(grToGLStencilOp));
             if (fTwoSidedStencilSupport) {
                 GrGLenum backFunc;