Reland "Add logging to external intent handling"

This is a reland of ba58fd11

Original change's description:
> Add logging to external intent handling
> 
> I will revert this CL after a few canaries.
> 
> Bug: 839751
> Change-Id: I823ec7c2eb47df905869d3f4f74c89e59a1433be
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2246596
> Auto-Submit: Jochen Eisinger <jochen@chromium.org>
> Reviewed-by: Ted Choc <tedchoc@chromium.org>
> Commit-Queue: Jochen Eisinger <jochen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#779391}

Bug: 839751
Change-Id: I620626407acbc482c7a7f6eee595dac57ee4ecf3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2252039
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Ted Choc <tedchoc@chromium.org>
Auto-Submit: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#779887}

components/external_intents/android/java/src/org/chromium/components/external_intents/ExternalNavigationHandler.java

@@ -70,7 +70,8 @@ public class ExternalNavigationHandler {
     private static final String TAG = "UrlHandler";
 
     // Enables debug logging on a local build.
-    private static final boolean DEBUG = false;
+    // TODO(jochen): switch this back to false.
+    private static final boolean DEBUG = true;
 
     private static final String WTAI_URL_PREFIX = "wtai://wp/";
     private static final String WTAI_MC_URL_PREFIX = "wtai://wp/mc;";

components/external_intents/android/java/src/org/chromium/components/external_intents/RedirectHandler.java

@@ -13,6 +13,7 @@ import android.text.TextUtils;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.IntentUtils;
+import org.chromium.base.Log;
 import org.chromium.base.PackageManagerUtils;
 import org.chromium.ui.base.PageTransition;
 
@@ -23,6 +24,7 @@ import java.util.List;
  * This class contains the logic to determine effective navigation/redirect.
  */
 public class RedirectHandler {
+    private static final String TAG = "RedirectHandler";
     /**
      * An invalid entry index.
      */
@@ -148,15 +150,30 @@ public class RedirectHandler {
         boolean isNewLoadingStartedByUser = false;
         boolean isFromIntent = pageTransitionCore == PageTransition.LINK
                 && (pageTransType & PageTransition.FROM_API) != 0;
+
+        Log.i(TAG,
+                "updateNewUrlLoading called (pageTransType: " + pageTransType
+                        + ", isRedirect: " + isRedirect + ", hasUserGesture: " + hasUserGesture
+                        + ", lastUserInteractionTime: " + lastUserInteractionTime
+                        + ", lastCommittedEntryIndex: " + lastCommittedEntryIndex + ")");
+        Log.i(TAG,
+                " - prevNewUrlLoadingTime: " + prevNewUrlLoadingTime
+                        + ", mLastNewUrlLoadingTime: " + mLastNewUrlLoadingTime);
+        Log.i(TAG,
+                " - pageTransitionCore: " + pageTransitionCore + ", isFromIntent: " + isFromIntent);
         if (!isRedirect) {
             if ((pageTransType & PageTransition.FORWARD_BACK) != 0) {
                 isNewLoadingStartedByUser = true;
+                Log.i(TAG, "- isNewLoadingStartedByUser: forward/back navigation");
             } else if (pageTransitionCore != PageTransition.LINK
                     && pageTransitionCore != PageTransition.FORM_SUBMIT) {
                 isNewLoadingStartedByUser = true;
+                Log.i(TAG, "- isNewLoadingStartedByUser: not a link or form submission");
             } else if (prevNewUrlLoadingTime == INVALID_TIME || isFromIntent
                     || lastUserInteractionTime > prevNewUrlLoadingTime) {
                 isNewLoadingStartedByUser = true;
+                Log.i(TAG,
+                        "- isNewLoadingStartedByUser: first load, from intent or new user gesture");
             }
         }
 
@@ -164,17 +181,22 @@ public class RedirectHandler {
             // Updates mInitialNavigationType for a new loading started by a user's gesture.
             if (isFromIntent && mInitialIntent != null) {
                 mInitialNavigationType = NAVIGATION_TYPE_FROM_INTENT;
+                Log.i(TAG, " - mInitialNavigationType: FROM_INTENT");
             } else {
                 clearIntentHistory();
                 if (pageTransitionCore == PageTransition.TYPED) {
                     mInitialNavigationType = NAVIGATION_TYPE_FROM_USER_TYPING;
+                    Log.i(TAG, " - mInitialNavigationType: USER_TYPING");
                 } else if (pageTransitionCore == PageTransition.RELOAD
                         || (pageTransType & PageTransition.FORWARD_BACK) != 0) {
                     mInitialNavigationType = NAVIGATION_TYPE_FROM_RELOAD;
+                    Log.i(TAG, " - mInitialNavigationType: RELOAD");
                 } else if (pageTransitionCore == PageTransition.LINK && !hasUserGesture) {
                     mInitialNavigationType = NAVIGATION_TYPE_FROM_LINK_WITHOUT_USER_GESTURE;
+                    Log.i(TAG, " - mInitialNavigationType: LINK_WITHOUT_USER_GESTURE");
                 } else {
                     mInitialNavigationType = NAVIGATION_TYPE_OTHER;
+                    Log.i(TAG, " - mInitialNavigationType: OTHER");
                 }
             }
             mIsOnEffectiveRedirectChain = false;
@@ -183,6 +205,9 @@ public class RedirectHandler {
         } else if (mInitialNavigationType != NAVIGATION_TYPE_NONE) {
             // Redirect chain starts from the second url loading.
             mIsOnEffectiveRedirectChain = true;
+            Log.i(TAG, " - mIsOnEffectiveRedirectChain: true");
+        } else {
+            Log.i(TAG, " - no updates");
         }
     }