Bug 1697979 - Part 1: Reuse previously built stacking context display items without merging r=mstange

Differential Revision: https://phabricator.services.mozilla.com/D128413
2022-01-20 18:38:59 +00:00
parent f9e4342a90
commit cc5862abeb
17 changed files with 595 additions and 109 deletions
--- a/layout/generic/nsTextFrame.cpp
+++ b/layout/generic/nsTextFrame.cpp
@@ -10293,8 +10293,9 @@ void nsTextFrame::ToCString(nsCString& aBuf) const {
    return;
  }

-  const uint32_t contentLength = AssertedCast<uint32_t>(GetContentLength());
-  if (0 == contentLength) {
+  const int32_t length = GetContentEnd() - mContentOffset;
+  if (length <= 0) {
+    // Negative lengths are possible during invalidation.
    return;
  }