Bug 1666415 - Skip checking for history load in E10SUtils for child process. r=smaug

With session history in the parent, all history loads needs to be
handled by the parent, which means that E10SUtils with session history
in the parent doesn't need to consider that to determine if a uri can
be loaded.

Differential Revision: https://phabricator.services.mozilla.com/D90961

toolkit/modules/E10SUtils.jsm

@@ -1032,23 +1032,25 @@ var E10SUtils = {
     }
 
     // Allow history load if loaded in this process before.
-    let requestedIndex = sessionHistory.legacySHistory.requestedIndex;
-    if (requestedIndex >= 0) {
-      this.log().debug("Checking history case\n");
-      if (
-        sessionHistory.legacySHistory.getEntryAtIndex(requestedIndex)
-          .loadedInThisProcess
-      ) {
-        this.log().info("History entry loaded in this process");
-        return true;
-      }
+    if (!sessionHistoryInParent) {
+      let requestedIndex = sessionHistory.legacySHistory.requestedIndex;
+      if (requestedIndex >= 0) {
+        this.log().debug("Checking history case\n");
+        if (
+          sessionHistory.legacySHistory.getEntryAtIndex(requestedIndex)
+            .loadedInThisProcess
+        ) {
+          this.log().info("History entry loaded in this process");
+          return true;
+        }
 
-      // If not originally loaded in this process allow it if the URI would
-      // normally be allowed to load in this process by default.
-      this.log().debug(
-        `Checking remote type, got: ${remoteType} want: ${wantRemoteType}\n`
-      );
-      return remoteType == wantRemoteType;
+        // If not originally loaded in this process allow it if the URI would
+        // normally be allowed to load in this process by default.
+        this.log().debug(
+          `Checking remote type, got: ${remoteType} want: ${wantRemoteType}\n`
+        );
+        return remoteType == wantRemoteType;
+      }
     }
 
     // If the URI can be loaded in the current process then continue