Reland "Enable GpuWatchdogV2 in Field trial testing for all platforms"

This reverts commit 7296d844.

Reason for revert: <Crashes caused by this CL has been fixed>

Original change's description:
> Revert "Enable GpuWatchdogV2 in Field trial testing for all platforms"
> 
> This reverts commit 752f7f2c.
> 
> Reason for revert: <Watchdog V2 causes crashes in the bots and it falls back to SwiftShader. bug 995372>
> 
> Original change's description:
> > Enable GpuWatchdogV2 in Field trial testing for all platforms
> > 
> > Bug: 949839
> > Change-Id: I5939069144719c501209af3cda3b7693f61f8866
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1682315
> > Commit-Queue: Maggie Chen <magchen@chromium.org>
> > Reviewed-by: Ilya Sherman <isherman@chromium.org>
> > Reviewed-by: Zhenyao Mo <zmo@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#688375}
> 
> TBR=isherman@chromium.org,zmo@chromium.org,magchen@chromium.org
> 
> Change-Id: I2f64da411b2289265c1a9657fae85c083953bfb8
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 949839
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761559
> Reviewed-by: Maggie Chen <magchen@chromium.org>
> Commit-Queue: Maggie Chen <magchen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#688690}

TBR=isherman@chromium.org,zmo@chromium.org,magchen@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 949839
Change-Id: Ib92ed2d060f278ca9c53e78edf06822cbb2f487a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1779222Reviewed-by: Maggie Chen <magchen@chromium.org>
Commit-Queue: Maggie Chen <magchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#692165}

testing/variations/fieldtrial_testing_config.json

@@ -2594,6 +2594,25 @@
             ]
         }
     ],
+    "GpuWatchdogV2": [
+        {
+            "platforms": [
+                "android",
+                "chromeos",
+                "linux",
+                "mac",
+                "windows"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled",
+                    "enable_features": [
+                        "GpuWatchdogV2"
+                    ]
+                }
+            ]
+        }
+    ],
     "GridLayoutForNtpShortcuts": [
         {
             "platforms": [