Make ShouldOverrideUrlLoadingInternal more readable (1 of N)

No functional changes intended, please revert if things break.

This function is a large, and hard to follow. I'm hoping to break out a
bunch of functions that are clearer about what they're doing and make
ordering clearer.

Bug: 1006927
Change-Id: I46815dd4f160f512c7abc13396b511d01faf18b3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1819820Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699622}

chrome/android/java/src/org/chromium/chrome/browser/tab/TabRedirectHandler.java

@@ -264,6 +264,8 @@ public class TabRedirectHandler extends EmptyTabObserver implements UserData {
      */
     public boolean shouldStayInChrome(boolean hasExternalProtocol,
             boolean isForTrustedCallingApp) {
+        // http://crbug/424029 : Need to stay in Chrome for an intent heading explicitly to Chrome.
+        // http://crbug/881740 : Relax stay in Chrome restriction for Custom Tabs.
         return (mIsInitialIntentHeadingToChrome && !hasExternalProtocol)
                 || shouldNavigationTypeStayInChrome(isForTrustedCallingApp);
     }