DevTools: Minor A11y change to Network DataGrid display

For users who don't use screen readers, the icon in the data grid
communicates information about the type of document in the data
grid. However, this icon lacked the document type information. This
change adds the name of the type to the icon so it can be read via
a screen reader.

Bug: 963183
Change-Id: I6b3e717b270467327856c502e6ba47329386b31a

https: //imgur.com/F0HyQ1L
https: //imgur.com/xo1kz07
Change-Id: I6b3e717b270467327856c502e6ba47329386b31a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1644380Reviewed-by: Joel Einbinder <einbinder@chromium.org>
Commit-Queue: Brandon Goddard <brgoddar@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#666520}

third_party/blink/renderer/devtools/front_end/network/NetworkDataGridNode.js

@@ -796,12 +796,14 @@ Network.NetworkRequestNode = class extends Network.NetworkNode {
     let iconElement;
     if (this._request.resourceType() === Common.resourceTypes.Image) {
       const previewImage = createElementWithClass('img', 'image-network-icon-preview');
+      UI.ARIAUtils.setAccessibleName(previewImage, this._request.resourceType().title());
       this._request.populateImageSource(previewImage);
 
       iconElement = createElementWithClass('div', 'icon');
       iconElement.appendChild(previewImage);
     } else {
       iconElement = createElementWithClass('img', 'icon');
+      UI.ARIAUtils.setAccessibleName(iconElement, this._request.resourceType().title());
     }
     iconElement.classList.add(this._request.resourceType().name());