turn off debugging printfs

fix pathops issues 1417, 1418

be more rigorous about pulling intersections of lines to end points
rewrite cubic/line and quad/line intersections to share style

BUG=

Review URL: https://codereview.chromium.org/19543005

git-svn-id: http://skia.googlecode.com/svn/trunk@10270 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pathops/SkPathOpsLine.cpp b/src/pathops/SkPathOpsLine.cpp
index 47c0565..48c042a 100644
--- a/src/pathops/SkPathOpsLine.cpp
+++ b/src/pathops/SkPathOpsLine.cpp
@@ -41,8 +41,13 @@
     return p0.cross(p2);
 }
 
-// OPTIMIZE: assert if t is 0 or 1 (caller shouldn't pass only 0/1)
-SkDPoint SkDLine::xyAtT(double t) const {
+SkDPoint SkDLine::ptAtT(double t) const {
+    if (0 == t) {
+        return fPts[0];
+    }
+    if (1 == t) {
+        return fPts[1];
+    }
     double one_t = 1 - t;
     SkDPoint result = { one_t * fPts[0].fX + t * fPts[1].fX, one_t * fPts[0].fY + t * fPts[1].fY };
     return result;
@@ -72,7 +77,7 @@
         return -1;
     }
     double t = numer / denom;
-    SkDPoint realPt = xyAtT(t);
+    SkDPoint realPt = ptAtT(t);
     SkDVector distU = xy - realPt;
     double distSq = distU.fX * distU.fX + distU.fY * distU.fY;
     double dist = sqrt(distSq); // OPTIMIZATION: can we compare against distSq instead ?