Remove unnecessary std::move(entry.break_token /* raw_pointer */).

This CL removes an unnecessary std::move - it is unnecessary, because

1) |entry.break_token| is MulticolPartWalker::Entry::break_token which
is a raw pointer (const NGBlockBreakToken*)

2) moves of built-in primitives types (including raw pointers) are just
   copies

Bug: 1080832, 1066617
Change-Id: I7e6d1d44620732824962560c39bf7c90c3f65bed
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2298336
Commit-Queue: Łukasz Anforowicz <lukasza@chromium.org>
Commit-Queue: Ian Kilpatrick <ikilpatrick@chromium.org>
Commit-Queue: Bartek Nowierski <bartekn@chromium.org>
Auto-Submit: Łukasz Anforowicz <lukasza@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Bartek Nowierski <bartekn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#788460}

third_party/blink/renderer/core/layout/ng/ng_column_layout_algorithm.cc

@@ -442,7 +442,7 @@ NGBreakStatus NGColumnLayoutAlgorithm::LayoutChildren() {
       if (entry.break_token) {
         // Copy unhandled incoming break tokens, for the next (outer)
         // fragmentainer.
-        container_builder_.AddBreakToken(std::move(entry.break_token));
+        container_builder_.AddBreakToken(entry.break_token);
       } else if (entry.spanner) {
         // Create break tokens for the spanners that were discovered (but not
         // handled) while laying out this (outer) fragmentainer, so that they