[Devtools] Added product entry tests for network

third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js

Index: third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js b/third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js
index 3f06fbf7460a19b31805a6c78a95db6c45c34ba9..6009ccbf91e967d3811c3d96199d38c3dc588bb1 100644
--- a/third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js
+++ b/third_party/WebKit/LayoutTests/http/tests/inspector/inspector-test.js
@@ -427,6 +427,27 @@ InspectorTest.dumpNavigatorViewInMode = function(view, mode)
     InspectorTest.dumpNavigatorView(view);
 }
 
+/**
+ * @param {symbol} event
+ * @param {!Common.Object} obj
+ * @param {(function(?):boolean)|undefined}
+ * @return {!Promise}
+ */
+InspectorTest.waitEventListener = function(event, obj, condition = undefined)
+{
+    condition = condition || function() { return true;};
+    return new Promise(resolve => {
+        obj.addEventListener(event, onEventFired);
+
+        function onEventFired(event) {
+            if (!condition(event.data))
+                return;
+            obj.removeEventListener(event, onEventFired);
+            resolve(event.data);
+        }
+    });
+}
+
 InspectorTest.waitForUISourceCode = function(urlSuffix, projectType)
 {
     function matches(uiSourceCode)