Only skip pipe playback for blurs GM in FIXED mode.

Only skip it when it would actually fail. Also add a comment
describing why it fails:

// SkCanvas::drawCircle, used by this test, performs a quick reject.
// The large size given to the device used by SkGPipeCanvas means that
// the device clip will not be set properly and circles will be
// rejected when in FIXED.

Review URL: https://codereview.appspot.com/6354058

git-svn-id: http://skia.googlecode.com/svn/trunk@4414 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/blurs.cpp b/gm/blurs.cpp
index a1f3ef0..bb688b9 100644
--- a/gm/blurs.cpp
+++ b/gm/blurs.cpp
@@ -17,9 +17,15 @@
     }
 
 protected:
+#ifdef SK_SCALAR_IS_FIXED
     virtual uint32_t onGetFlags() const SK_OVERRIDE {
+        // SkCanvas::drawCircle, used by this test, performs a quick reject.
+        // The large size given to the device used by SkGPipeCanvas means that
+        // the device clip will not be set properly and circles will be
+        // rejected when in FIXED.
         return this->INHERITED::onGetFlags() | GM::kSkipPipe_Flag;
     }
+#endif
 
     virtual SkString onShortName() {
         return SkString("blurs");