Add more debugging for newly failing assert (DM on Xoom bots).

BUG=skia:

Review URL: https://codereview.chromium.org/568823002
diff --git a/src/core/SkGeometry.cpp b/src/core/SkGeometry.cpp
index 646dfb0..254f79b 100644
--- a/src/core/SkGeometry.cpp
+++ b/src/core/SkGeometry.cpp
@@ -102,7 +102,7 @@
     if (SkScalarIsNaN(r)) {
         return 0;
     }
-    SkASSERT(r >= 0 && r < SK_Scalar1);
+    SkASSERTF(r >= 0 && r < SK_Scalar1, "numer %f, denom %f, r %f", numer, denom, r);
     if (r == 0) { // catch underflow if numer <<<< denom
         return 0;
     }