Auto merge of #10246 - mbrubeck:strip-leading, r=pcwalton

Restore stripped whitespace before reflowing text fragments

Fixes #10200. r? @pcwalton

Note: The reftest uses a transition of non-zero duration, because I couldn't find any other way to reproduce the bug.  Unfortunately this makes it unreliable in debug builds. I tried to fix this using reftest-wait with setTimeout and requestAnimationFrame, but it still wouldn't complete the animation consistently.  To make the test work in debug builds we may need `transitionend` events (#10245) or a different way to reproduce the bug.

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1 files changed, 3 insertions, 0 deletions

diff --git a/components/layout/inline.rs b/components/layout/inline.rs
index cd2a822f317..228ef6c9f20 100644
--- a/components/layout/inline.rs
+++ b/components/layout/inline.rs
@@ -527,6 +527,9 @@ impl LineBreaker {
                        mut fragment: Fragment,
                        flow: &InlineFlow,
                        layout_context: &LayoutContext) {
+        // Undo any whitespace stripping from previous reflows.
+        fragment.reset_text_range_and_inline_size();
+
         // Determine initial placement for the fragment if we need to.
         //
         // Also, determine whether we can legally break the line before, or inside, this fragment.