gpu: Make gpu_perftests run and pass on mac.

gpu/perftests/texture_upload_perftest.cc

Index: gpu/perftests/texture_upload_perftest.cc
diff --git a/gpu/perftests/texture_upload_perftest.cc b/gpu/perftests/texture_upload_perftest.cc
index 18bc5ff5fd6894a118e14d0a33cfeb9167408355..2e9ef6cea4346d217eeae515b89db88f9e0cf40f 100644
--- a/gpu/perftests/texture_upload_perftest.cc
+++ b/gpu/perftests/texture_upload_perftest.cc
@@ -33,7 +33,7 @@ SHADER(
   varying vec2 v_texCoord;
   void main() {
     gl_Position = vec4(a_position.x, a_position.y, 0.0, 1.0);
-    v_texCoord = vec2((a_position.x + 1) * 0.5, (a_position.y + 1) * 0.5);
+    v_texCoord = vec2((a_position.x + 1.0) * 0.5, (a_position.y + 1.0) * 0.5);
   }
 );
 const char kFragmentShader[] =