fix symbol for intersection

Bug: skia:
Change-Id: I51e85eeba9975d20d897672f44935f573654619d
Reviewed-on: https://skia-review.googlesource.com/104141
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>

include/core/SkCoverageMode.h

@@ -19,7 +19,7 @@
  */
 enum class SkCoverageMode {
     kUnion,             // A ∪ B    A+B-A*B
-    kIntersect,         // A ∪ B    A*B
+    kIntersect,         // A ∩ B    A*B
     kDifference,        // A - B    A*(1-B)
     kReverseDifference, // B - A    B*(1-A)
     kXor,               // A ⊕ B    A+B-2*A*B