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This switches some "hot" targets to the "optimize_max" compiler config.
The "hot" targets have been picked base on the go/cwp data, this CL
makes the assumption that the hotness of the code is more or less the
same on different platforms (which seems like a fair assumption for
things like Mojo and //net).

Pinpoint will be used to evaluate the exact impact of this CL on metrics,
local benchmarks (with Speedometer 2.0) shows a 4% performance
improvement (based on the average after 5 runs of the Speedometer 2.0
benchmark).

The downside is that it makes the size of chrome.dll increase by 1.08MB
(~0.8%).

The change consist in adding this to the config of the hot targets:
  if (!is_debug) {
    configs -= [ "//build/config/compiler:default_optimization" ]
    configs += [ "//build/config/compiler:optimize_max" ]
  }
There's no |is_win| condition here as this is a noop on all platforms
other than Windows, see
https://cs.chromium.org/chromium/src/build/config/compiler/BUILD.gn?rcl=3a8f3f7de7291ccb2045a285965daf4053ac5739
The "optimize" config on !is_win is usually:
  cflags = [ "-O2" ] + common_optimize_on_cflags
which is the same as the "optimize_max" config for these same targets.

Bug: 1059861
Change-Id: Ib28781c7e56943650725fec9c50aa11bef413fbd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2095339Reviewed-by: Reid Kleckner <rnk@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Sébastien Marchand <sebmarchand@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749479}