Fix clip expansion in SkPictureRecord::recordRestoreOffsetPlaceholder()

src/core/SkPictureRecord.cpp

Index: src/core/SkPictureRecord.cpp
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index 2c2d334caf02d03dd3ee831550d851c4cccf2d22..33071ee6a07554c1ff223214978dccb72512d20b 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -715,21 +715,28 @@ void SkPictureRecord::recordRestoreOffsetPlaceholder(SkRegion::Op op) {
         return;
     }
 
+    // The RestoreOffset field is initially filled with a placeholder
+    // value that points to the offset of the previous RestoreOffset
+    // in the current stack level, thus forming a linked list so that
+    // the restore offsets can be filled in when the corresponding
+    // restore command is recorded.
+    int32_t prevOffset = fRestoreOffsetStack.top();
+
     if (regionOpExpands(op)) {
         // Run back through any previous clip ops, and mark their offset to
         // be 0, disabling their ability to trigger a jump-to-restore, otherwise
         // they could hide this clips ability to expand the clip (i.e. go from
         // empty to non-empty).
         fillRestoreOffsetPlaceholdersForCurrentStackLevel(0);
+

[robertphillips, 2013/08/27 15:08:56]

Reset the pointer back to the previous clip so that ...

+        // Avoid linking to the previous RestoreOffset - otherwise a
+        // subsequent restore() will simply overwrite the offsets we just
+        // cleared.
+        prevOffset = 0;
     }
 
     size_t offset = fWriter.size();
-    // The RestoreOffset field is initially filled with a placeholder
-    // value that points to the offset of the previous RestoreOffset
-    // in the current stack level, thus forming a linked list so that
-    // the restore offsets can be filled in when the corresponding
-    // restore command is recorded.
-    addInt(fRestoreOffsetStack.top());
+    addInt(prevOffset);
     fRestoreOffsetStack.top() = offset;
 }