commit 14bd2353e018993e07996f570cd58c2b3520d40f
author xiaochengh <xiaochengh@chromium.org> Wed Jul 06 10:45:46 2016
committer Commit bot <commit-bot@chromium.org> Wed Jul 06 10:47:43 2016
tree 2dae40fc820f28238fc3b4f0f3636dbdf31b6238
parent 485ff73a6daeed372189a91ff19edb88ebea18b0

Use RelocatablePosition in CompositeEditCommand::moveParagraphs()

Currently, CompositeEditCommand::moveParagraphs() uses a pair of
VisiblePositions to keep track of original position of the moved
paragraph after it's moved away. However, the VisiblePositions may
be invalidated if their anchor nodes are moved out of document,
causing crashes when the VisiblePositions are used later. It causes
the failure of layout test:

fast/text/first-letter-bad-line-boxes-crash.html

This patch uses RelocatablePosition for the tracking purpose as
a bug fix.

BUG=581038
TEST=fast/text/first-letter-bad-line-boxes-crash.html

Review-Url: https://codereview.chromium.org/2127503002
Cr-Commit-Position: refs/heads/master@{#403879}