Re-enable trimMiddle tests and disable escapeForRegExp test

R=szuend@chromium.org

Bug: 1050549
Change-Id: Id404e0427b150b6301c3b73bf3a5eecfe871781c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2637501
Auto-Submit: Tim van der Lippe <tvanderlippe@chromium.org>
Commit-Queue: Simon Zünd <szuend@chromium.org>
Reviewed-by: Simon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#844811}

third_party/blink/web_tests/TestExpectations

@@ -5896,5 +5896,4 @@ crbug.com/1167222 http/tests/websocket/multiple-connections-throttled.html [ Pas
 crbug.com/1167309 fast/canvas/canvas-createImageBitmap-drawImage.html [ Pass Failure ]
 
 # DevTools roll
-crbug.com/1050549 http/tests/devtools/network/network-search.js [ Skip ]
-crbug.com/1050549 http/tests/devtools/tracing/timeline-misc/timeline-aggregated-details.js [ Skip ]
+crbug.com/1050549 http/tests/devtools/network/preview-searchable.js [ Pass Failure ]

third_party/blink/web_tests/http/tests/devtools/network/network-search.js

@@ -81,7 +81,8 @@
     const link = lastResult.listItemElement.getElementsByClassName('devtools-link')[0];
     link.click();
     const requestNode = await networkItemSelected();
-    TestRunner.addResult(`Selected Node Name: ${requestNode._request.name().trimMiddle(100)}, URL: ${requestNode._request.url()}`);
+    const requestName = requestNode._request.name();
+    TestRunner.addResult(`Selected Node Name: ${requestName.substr(requestName.length - 100)}, URL: ${requestNode._request.url()}`);
     TestRunner.completeTest();
   }
 })();