Complete UI thread blob/filesystem URL blocking and remove IO thread check.

chrome/browser/extensions/process_manager_browsertest.cc

Index: chrome/browser/extensions/process_manager_browsertest.cc
diff --git a/chrome/browser/extensions/process_manager_browsertest.cc b/chrome/browser/extensions/process_manager_browsertest.cc
index a178d84b66c68c5b8da8a1751c6a0fdbaf2387e0..8e8c10430a49d3caa8bd1f923e48ede9ca6056bf 100644
--- a/chrome/browser/extensions/process_manager_browsertest.cc
+++ b/chrome/browser/extensions/process_manager_browsertest.cc
@@ -945,14 +945,6 @@ IN_PROC_BROWSER_TEST_F(ProcessManagerBrowserTest,
 // WebViewTest.Shim_TestBlobURL.
 IN_PROC_BROWSER_TEST_F(ProcessManagerBrowserTest,
                        NestedURLNavigationsToAppBlocked) {
-  // TODO(alexmos):  Re-enable this test for PlzNavigate after tightening
-  // nested URL blocking for apps with the "webview" permission in
-  // ExtensionNavigationThrottle and removing the corresponding check from
-  // ChromeExtensionsNetworkDelegate.  The latter is incompatible with
-  // PlzNavigate.
-  if (content::IsBrowserSideNavigationEnabled())
-    return;
-
   // Disabling web security is necessary to test the browser enforcement;
   // without it, the loads in this test would be blocked by
   // SecurityOrigin::canDisplay() as invalid local resource loads.