path ops -- use standard max, min, double-is-nan

fix a comment or two as well
Review URL: https://codereview.chromium.org/13934009

git-svn-id: http://skia.googlecode.com/svn/trunk@8822 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pathops/SkPathOpsQuad.cpp b/src/pathops/SkPathOpsQuad.cpp
index cbba2a3..685f49e 100644
--- a/src/pathops/SkPathOpsQuad.cpp
+++ b/src/pathops/SkPathOpsQuad.cpp
@@ -26,7 +26,7 @@
     int roots = SkDCubic::RootsValidT(a, b, c, d, ts);
     double d0 = pt.distanceSquared(fPts[0]);
     double d2 = pt.distanceSquared(fPts[2]);
-    double distMin = SkTMin<double>(d0, d2);
+    double distMin = SkTMin(d0, d2);
     int bestIndex = -1;
     for (int index = 0; index < roots; ++index) {
         SkDPoint onQuad = xyAtT(ts[index]);