AW UMA: delete fieldtrial config for WebViewCollectNonEmbeddedMetrics

WebViewCollectNonEmbeddedMetrics feature flag has been removed in
crrev.com/c/2252082 and there is no need to test this config any more.

Bug: 1001185, b/157911640
Test: N/A
Change-Id: I1c94b1c24f8b8a488eef94f4ccd5697ca2043643
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2283210
Commit-Queue: Steven Holte <holte@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Auto-Submit: Hazem Ashmawy <hazems@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#786158}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: aee069038a5806a16bb58893d55d894e0c318dc9
1 file changed