Revert "Roll SwiftShader 4d3efed..aadf3e1"

This reverts commit f42ff9b5.

Reason for revert: Still fails Win7 (dbg) telemetry tests

Original change's description:
> Roll SwiftShader 4d3efed..aadf3e1
> 
> https://swiftshader.googlesource.com/SwiftShader.git/+log/4d3efed..aadf3e1
> 
> BUG=
> 
> TBR=kbr@chromium.org
> 
> TEST=bots
> 
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel,linux_chromium_cfi_rel_ng;master.tryserver.chromium.android:android_optional_gpu_tests_rel
> 
> Change-Id: Ifdfd2e7f511023cf036eee83f50ddc7980b0b783
> Reviewed-on: https://chromium-review.googlesource.com/600892
> Reviewed-by: Alexis Hétu <sugoi@chromium.org>
> Commit-Queue: Alexis Hétu <sugoi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#491871}

TBR=sugoi@chromium.org,kbr@chromium.org

Change-Id: I5ef897b46cbb4455b0b39a541eee4c383350baf3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel, linux_chromium_cfi_rel_ng;master.tryserver.chromium.android:android_optional_gpu_tests_rel
Reviewed-on: https://chromium-review.googlesource.com/601443Reviewed-by: Alexis Hétu <sugoi@chromium.org>
Commit-Queue: Alexis Hétu <sugoi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491887}

DEPS

@@ -60,7 +60,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.
-  'swiftshader_revision': 'aadf3e1325f17141d033947dd23020a852251d94',
+  'swiftshader_revision': '4d3efedb10ce60bdb7847336eba0360fdc9af9d3',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling PDFium
   # and whatever else without interference from each other.