Remove command line/field trial support and configs for Isolate Extensions.

chrome/browser/extensions/api/extension_action/browser_action_apitest.cc

Index: chrome/browser/extensions/api/extension_action/browser_action_apitest.cc
diff --git a/chrome/browser/extensions/api/extension_action/browser_action_apitest.cc b/chrome/browser/extensions/api/extension_action/browser_action_apitest.cc
index 72258326412ebdbdc85a7b754950b5408d5a719f..da79d2e5d26df0ac300c98ed66458ca757ba68a8 100644
--- a/chrome/browser/extensions/api/extension_action/browser_action_apitest.cc
+++ b/chrome/browser/extensions/api/extension_action/browser_action_apitest.cc
@@ -735,9 +735,9 @@ IN_PROC_BROWSER_TEST_F(BrowserActionApiTest, TestTriggerBrowserAction) {
   EXPECT_EQ(result, "red");
 }
 
-// Test that a browser action popup with a web iframe works correctly. This
-// primarily targets --isolate-extensions and --site-per-process modes, where
-// the iframe runs in a separate process.  See https://crbug.com/546267.
+// Test that a browser action popup with a web iframe works correctly. The
+// iframe is expected to run in a separate process.
+// See https://crbug.com/546267.
 IN_PROC_BROWSER_TEST_F(BrowserActionApiTest, BrowserActionPopupWithIframe) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
@@ -953,31 +953,12 @@ class NavigatingExtensionPopupBrowserTest : public BrowserActionApiTest {
 IN_PROC_BROWSER_TEST_F(NavigatingExtensionPopupBrowserTest, Webpage) {
   GURL web_url(embedded_test_server()->GetURL("foo.com", "/title1.html"));
 
-  // With and without --isolate-extension the GET request will be blocked in
-  // ExtensionViewHost::OpenURLFromTab (which silently drops navigations with
-  // CURRENT_TAB disposition).
+  // The GET request will be blocked in ExtensionViewHost::OpenURLFromTab
+  // (which silently drops navigations with CURRENT_TAB disposition).
   TestPopupNavigationViaGet(web_url, EXPECTING_NAVIGATION_FAILURE);
 
   // POST requests don't go through ExtensionViewHost::OpenURLFromTab.
-  //
-  // Without --isolate-extensions, there is no process transfer to isolate
-  // extensions into separate processes and therefore
-  // 1) navigating a popup extension to a webpage will succeed (because
-  //    ExtensionViewHost::ShouldTransferNavigation won't get called when there
-  //    is no transfer),
-  // 2) the webpage will stay in the same renderer process.
-  // This behavior is okay without --isolate-extensions (where webpages and
-  // extensions can coexist in the same process in other scenarios) - therefore
-  // no test verification is needed in this case.
-  //
-  // With --isolate-extensions the navigation should be blocked by
-  // ExtensionViewHost::ShouldTransferNavigation.  Test verification is
-  // important in --isolate-extensions mode, because this mode is all about
-  // isolating extensions and webpages into separate processes and therefore we
-  // need to ensure the behavior described above doesn't occur (i.e. that
-  // instead the webpage navigation in an extension popup fails).
-  if (extensions::IsIsolateExtensionsEnabled())
-    TestPopupNavigationViaPost(web_url, EXPECTING_NAVIGATION_FAILURE);
+  TestPopupNavigationViaPost(web_url, EXPECTING_NAVIGATION_FAILURE);
 }
 
 // Tests that an extension pop-up can be navigated to another page