DevTools: Fix and reenable Watch expression tests

This CL fixes and re-enables tests that will be broken by
https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/1884528

Bug: 963183
Change-Id: Ia783efb3b292a143108cf92def3821c6f22893fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1811866Reviewed-by: Lorne Mitchell <lomitch@microsoft.com>
Commit-Queue: Jack Lynch <jalyn@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#714767}

third_party/blink/web_tests/TestExpectations

@@ -5877,12 +5877,8 @@ crbug.com/1021407 [ Retina Release ] virtual/audio-service/media/video-controls-
 crbug.com/1021407 [ Mac10.11 ] virtual/audio-service/media/controls/video-overlay-cast-dark-rendering.html [ Pass Failure ]
 crbug.com/1021407 [ Mac10.11 ] media/controls/video-overlay-cast-dark-rendering.html [ Pass Failure ]
 
-# Temporarily disabled to land accessibility changes in DevTools
-crbug.com/963183 http/tests/devtools/sources/debugger-ui/error-in-watch-expressions.js [ Pass Failure ]
-crbug.com/963183 http/tests/devtools/sources/debugger-ui/watch-expressions-preserve-expansion.js [ Pass Failure ]
-crbug.com/963183 http/tests/devtools/sources/debugger/debugger-proto-property.js [ Pass Failure ]
-
 # Temporarily disabled to land scope changes in DevTools
 crbug.com/963183 http/tests/devtools/sources/debugger-pause/set-return-value.js [ Pass Failure ]
+crbug.com/963183 http/tests/devtools/sources/debugger/debugger-proto-property.js [ Pass Failure ]
 
 crbug.com/892983 external/wpt/css/css-pseudo/first-line-with-before-after.html [ Failure ]

third_party/blink/web_tests/http/tests/devtools/sources/debugger-ui/error-in-watch-expressions.js

@@ -20,7 +20,7 @@
 
   function step1() {
     TestRunner.addResult(
-        watchExpressionsPane.contentElement.textContent.indexOf('<not available>') !== -1 ? 'SUCCESS' : 'FAILED');
+        watchExpressionsPane.contentElement.deepTextContent().indexOf('<not available>') !== -1 ? 'SUCCESS' : 'FAILED');
 
     // Clear watch expressions after execution.
     watchExpressionsPane._deleteAllButtonClicked();

third_party/blink/web_tests/http/tests/devtools/sources/debugger-ui/watch-expressions-preserve-expansion.js

@@ -71,9 +71,9 @@
       var watch = pane._watchExpressions[i];
       TestRunner.addResult(
           watch.expression() + ': ' +
-          watch._objectPropertiesSection._object._description);
+          watch._treeElement._object._description);
       dumpObjectPropertiesTreeElement(
-          watch._objectPropertiesSection.objectTreeElement(), '  ');
+          watch._treeElement, '  ');
     }
   }
 
@@ -89,10 +89,11 @@
       dumpObjectPropertiesTreeElement(treeElement.children()[i], '  ' + indent);
   }
 
-  function expandProperties(treeoutline, path, callback) {
-    treeoutline.addEventListener(
+  function expandProperties(watchExpressionTreeElement, path, callback) {
+    const treeOutline = watchExpressionTreeElement.treeOutline;
+    treeOutline.addEventListener(
         UI.TreeOutline.Events.ElementAttached, elementAttached);
-    treeoutline.expand();
+    watchExpressionTreeElement.expand();
 
     function elementAttached(event) {
       var treeElement = event.data;
@@ -111,7 +112,7 @@
         return;
       }
 
-      treeoutline.removeEventListener(
+      treeOutline.removeEventListener(
           UI.TreeOutline.Events.ElementAttached, elementAttached);
       callback();
     }
@@ -123,7 +124,7 @@
     for (var i = 0; i < pane._watchExpressions.length; i++) {
       var watch = pane._watchExpressions[i];
       if (watch.expression() === expression) {
-        expandProperties(watch._objectPropertiesSection, path, callback);
+        expandProperties(watch._treeElement, path, callback);
         break;
       }
     }