Revert "Test: MHTML document loaded inside a data-URL parent."

This reverts commit 631cf612.

Reason for revert:

Findit (https://goo.gl/kROfz5) identified CL at revision 665876 as the
culprit for failures in the build cycles as shown on:
https://analysis.chromium.org/waterfall/culprit?key=ag9zfmZpbmRpdC1mb3ItbWVyRAsSDVdmU3VzcGVjdGVkQ0wiMWNocm9taXVtLzYzMWNmNjEyZTg4YmUzZWIyMWQ0MmY2ZTFjYzYxZjk3NDlmYWY3OGUM

Sample Failed Build: https://ci.chromium.org/buildbot/chromium.memory/Mac%20ASan%2064%20Tests%20%281%29/53748

Sample Failed Step: content_browsertests

Original change's description:
> Test: MHTML document loaded inside a data-URL parent.
> 
> In an MHTML document, blink::DocumentLoader::archive_ is transmitted
> from parent to children. data-URL aren't loaded from the MHTML archive.
> In this case, does it means children of data-URL aren't able to be
> loaded from the MHTML archive? Hopefully, it is currently working. They
> are able to load from the MHTML document, because |archive_| continue to
> be transmitted.
> 
> This CL adds a test to ensure this continue to work in the future.
> 
> Bug: None.
> Change-Id: Icb51dc48691112cf9e45dfe8cb81d389544a0c41
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1635669
> Commit-Queue: Arthur Sonzogni <arthursonzogni@chromium.org>
> Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#665876}


Change-Id: Iab5a838b789e845537a3a81a8f87cd54516b1162
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: None.
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1643089
Cr-Commit-Position: refs/heads/master@{#665896}

content/browser/navigation_mhtml_browsertest.cc

@@ -413,35 +413,4 @@ IN_PROC_BROWSER_TEST_F(NavigationMhtmlBrowserTest, IframeContentIdNotFound) {
   EXPECT_FALSE(iframe_navigation.is_error());
 }
 
-// Check MHTML subframe works when its parent is loaded from a data-URL.
-//
-// Frame tree: a1(a2(a3))
-//  -  a1: The main document. Loaded from the MHTML archive.
-//  -  a2: An sub-document loaded from a data-URL.
-//  -  a3: A sub-sub-document loaded from the MHTML archive.
-IN_PROC_BROWSER_TEST_F(NavigationMhtmlBrowserTest, MhtmlIframeInsideDataUrl) {
-  MhtmlArchive mhtml_archive;
-  mhtml_archive.AddHtmlDocument(
-      GURL("http://example.com/a1.html"),
-      "<iframe src=\"data:text/html,"
-      "  <iframe src=&quot;http://example.com/a3.html&quot;></iframe>"
-      "\"></iframe>");
-  mhtml_archive.AddHtmlDocument(GURL("http://example.com/a3.html"),
-                                "<iframe></iframe>");
-  GURL mhtml_url = mhtml_archive.Write("index.mhtml");
-
-  EXPECT_TRUE(NavigateToURL(shell(), mhtml_url));
-
-  RenderFrameHostImpl* a1_rfh = main_frame_host();
-  ASSERT_EQ(1u, a1_rfh->child_count());
-  RenderFrameHostImpl* a2_rfh = a1_rfh->child_at(0)->current_frame_host();
-  ASSERT_EQ(1u, a2_rfh->child_count());
-
-  // Check a3 is properly loaded. EvalJs("document.body.innerHTML") can't be
-  // used, because javascript is disabled. Instead, check it was able to load an
-  // iframe.
-  RenderFrameHostImpl* a3_rfh = a2_rfh->child_at(0)->current_frame_host();
-  ASSERT_EQ(1u, a3_rfh->child_count());
-}
-
 }  // namespace content