Fix bounds of checking if a radii are too long for a side.

fuzz/FuzzScaleToSides.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 // Reminder of how to run:
 //  $ env CC=afl-clang CXX=afl-clang++ ./gyp_skia
 //  $ ninja -C out/Debug fuzz
 //  $ afl-fuzz -i fuzz-in -o fuzz-out out/Debug/fuzz -n ScaleToSides -b @@
 // where you seed fuzz-in/ with one or more small files.
 
 #include "Fuzz.h"
 #include "SkScaleToSides.h"
 #include <cmath>
 
 DEF_FUZZ(ScaleToSides, fuzz) {
     float radius1 = fuzz->nextF(),
           radius2 = fuzz->nextF(),
           width   = fuzz->nextF();
-    SkDebugf("%g %g %g\n", radius1, radius2, width);
 
     if (!std::isfinite(radius1) ||
         !std::isfinite(radius2) ||
-        !std::isfinite(width))
+        !std::isfinite(width)   ||
+        radius1 <= 0.0f         ||
+        radius2 <= 0.0f         ||
+        width <= 0.0f)
     {
         fuzz->signalBoring();
     }
 
-    if (width <= 0.0f) {
+    double scale = (double)width / ((double)radius1 + (double)radius2);
+    if (scale >= 1.0 || scale <= 0.0) {
         fuzz->signalBoring();
     }
-
-    double scale = (double)width / ((double)radius1 + (double)radius2);
-    if (scale >= 1.0) {
-        fuzz->signalBoring();
-    }
+    SkDebugf("%g %g %g %g\n", radius1, radius2, width, scale);
     ScaleToSides::AdjustRadii(width, scale, &radius1, &radius2);
 
     // TODO(mtklein): add fuzz->keepResult()
     volatile float junk = 0.0f;
     junk *= radius1;
     junk *= radius2;
 }