Change cross-origin isolated DCHECK, add history tests

The equality of the "cross origin isolated" value should not be checked
if it's still speculative, and some other cases covered by
IsSiteInstanceCompatibleWithCoopCoepCrossOriginIsolation.

Bug: 1107814, 1096135
Change-Id: I37152bbc348d598dc4612666bfc181da60e75555
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2385255
Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Arthur Hemery <ahemery@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804854}

content/browser/cross_origin_opener_policy_browsertest.cc

@@ -1984,6 +1984,27 @@ IN_PROC_BROWSER_TEST_P(CrossOriginOpenerPolicyBrowserTest,
     EXPECT_FALSE(current_si->IsRelatedSiteInstance(previous_si.get()));
   }
 
+  // Back navigation from a cross-origin isolated page to a non cross-origin
+  // isolated page.
+  {
+    EXPECT_TRUE(NavigateToURL(shell(), isolated_page));
+    scoped_refptr<SiteInstanceImpl> cross_origin_isolated_site_instance =
+        current_frame_host()->GetSiteInstance();
+
+    EXPECT_TRUE(
+        cross_origin_isolated_site_instance->IsCoopCoepCrossOriginIsolated());
+    web_contents()->GetController().GoBack();
+    EXPECT_TRUE(WaitForLoadStop(web_contents()));
+
+    scoped_refptr<SiteInstanceImpl> non_cross_origin_isolated_site_instance =
+        current_frame_host()->GetSiteInstance();
+
+    EXPECT_FALSE(non_cross_origin_isolated_site_instance
+                     ->IsCoopCoepCrossOriginIsolated());
+    EXPECT_FALSE(non_cross_origin_isolated_site_instance->IsRelatedSiteInstance(
+        cross_origin_isolated_site_instance.get()));
+  }
+
   // Cross origin navigation in between two cross-origin isolated pages.
   {
     EXPECT_TRUE(NavigateToURL(shell(), isolated_page));

content/browser/frame_host/render_frame_host_manager.cc

@@ -1562,8 +1562,9 @@ RenderFrameHostManager::GetSiteInstanceForNavigation(
       ConvertToSiteInstance(new_instance_descriptor, candidate_instance);
   SiteInstanceImpl* new_instance_impl =
       static_cast<SiteInstanceImpl*>(new_instance.get());
-  DCHECK_EQ(is_coop_coep_cross_origin_isolated,
-            new_instance_impl->IsCoopCoepCrossOriginIsolated());
+  DCHECK(IsSiteInstanceCompatibleWithCoopCoepCrossOriginIsolation(
+      new_instance_impl, frame_tree_node_->IsMainFrame(), dest_url,
+      is_coop_coep_cross_origin_isolated, is_speculative));
 
   // If |should_swap| is true, we must use a different SiteInstance than the
   // current one. If we didn't, we would have two RenderFrameHosts in the same

content/browser/frame_host/render_frame_host_manager_browsertest.cc

@@ -6731,9 +6731,8 @@ class ProactivelySwapBrowsingInstancesSameSiteCoopTest
 // COOP + COEP, should use new process).
 // 2. Go back to A2 (should use new process).
 // 3. Go back to A1 (should reuse A2's process).
-// Note: This test is currently disabled due to crbug.com/1107814.
 IN_PROC_BROWSER_TEST_P(ProactivelySwapBrowsingInstancesSameSiteCoopTest,
-                       DISABLED_HistoryNavigationReusesProcess_COOP) {
+                       HistoryNavigationReusesProcess_COOP) {
   // This test expects a renderer process to eventually get deleted when we
   // navigate away from the page using it, which won't happen if the page is
   // kept alive in the back-forward cache.  So, we should disable back-forward