Revert "Use the LegacyLinker instead of the ModernLinker"

This reverts commit fdb3188391eac0cee74a762e7bdbb4dbad315c30.

Reason for revert: Causing VR segfaults https://logs.chromium.org/v/?s=chromium%2Fbb%2Fchromium.fyi%2FAndroid_VR_Tests%2F13834%2F%2B%2Frecipes%2Fsteps%2Fstack_tool_with_logcat_dump%2F0%2Fstdout

Original change's description:
> Use the LegacyLinker instead of the ModernLinker
> 
> Remove the ModernLinker since it becomes unused. Also remove the possibility to
> set the linker differently in tests.
> 
> Public document explaining the motivation: https://goo.gl/kWnHYr
> 
> BUG=719977 (google-internal)
> 
> Change-Id: I5b9b85817093b36127fa4a607bced57b4350a5b8
> Reviewed-on: https://chromium-review.googlesource.com/538582
> Commit-Queue: Egor Pasko <pasko@chromium.org>
> Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
> Reviewed-by: Richard Coles <torne@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#517838}

TBR=pasko@chromium.org,yfriedman@chromium.org,torne@chromium.org

Change-Id: I638bd3223567a5a40babd036feca310257deaa6f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 719977 (google-internal)
Reviewed-on: https://chromium-review.googlesource.com/779921
Reviewed-by: Brian Sheedy <bsheedy@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517889}

CrOS-Libchrome-Original-Commit: 39a3080e58db0402c96231033dfc8cfd52e74de4
5 files changed
tree: 9753dc15d93e91deb6d65db25161806951fe6dbd
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/