rename sk_float_isNaN to sk_float_isnan to match related functions
add sk_float_isinf returning non-zero if the argument is +/- infinity



git-svn-id: http://skia.googlecode.com/svn/trunk@2813 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/MathBench.cpp b/bench/MathBench.cpp
index ffee901..9feb5af 100644
--- a/bench/MathBench.cpp
+++ b/bench/MathBench.cpp
@@ -186,7 +186,7 @@
 }
 
 static bool isfinite_plus_float(const float data[4]) {
-    return  !sk_float_isNaN(mulzeroadd(data));
+    return  !sk_float_isnan(mulzeroadd(data));
 }
 
 static bool isfinite_plus_mulzero(const float data[4]) {
@@ -212,11 +212,6 @@
 
 #undef MAKEREC
 
-static bool SkScalarIsNaN_new(SkScalar x) {
-    float y = x * 0;
-    return y == y;
-}
-
 static bool isFinite(const SkRect& r) {
     // x * 0 will be NaN iff x is infinity or NaN.
     // a + b will be NaN iff either a or b is NaN.