Make ShouldOverrideUrlLoadingInternal more readable (3 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: I5c0efdb274222b1af861acf7cd31dade9a3ab2a7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1822509
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699892}

chrome/android/java/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandler.java

@@ -344,6 +344,73 @@ public class ExternalNavigationHandler {
         return true;
     }
 
+    // http://crbug.com/159153: Don't override navigation from a chrome:* url to http or https.
+    // For example when clicking a link in bookmarks or most visited. When navigating from such
+    // a page, there is clear intent to complete the navigation in Chrome.
+    private boolean isLinkFromChromeInternalPage(ExternalNavigationParams params) {
+        if (params.getReferrerUrl() == null) return false;
+        if (params.getReferrerUrl().startsWith(UrlConstants.CHROME_URL_PREFIX)
+                && (params.getUrl().startsWith(UrlConstants.HTTP_URL_PREFIX)
+                        || params.getUrl().startsWith(UrlConstants.HTTPS_URL_PREFIX))) {
+            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Link from an internal chrome:// page");
+            return true;
+        }
+        return false;
+    }
+
+    private boolean handleWtaiMcProtocol(ExternalNavigationParams params) {
+        if (!params.getUrl().startsWith(WTAI_MC_URL_PREFIX)) return false;
+        // wtai://wp/mc;number
+        // number=string(phone-number)
+        mDelegate.startActivity(
+                new Intent(Intent.ACTION_VIEW,
+                        Uri.parse(WebView.SCHEME_TEL
+                                + params.getUrl().substring(WTAI_MC_URL_PREFIX.length()))),
+                false);
+        if (DEBUG) Log.i(TAG, "OVERRIDE_WITH_EXTERNAL_INTENT wtai:// link handled");
+        RecordUserAction.record("Android.PhoneIntent");
+        return true;
+    }
+
+    private boolean isUnhandledWtaiProtocol(ExternalNavigationParams params) {
+        if (!params.getUrl().startsWith(WTAI_URL_PREFIX)) return false;
+        if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Unsupported wtai:// link");
+        return true;
+    }
+
+    // The "about:", "chrome:", "chrome-native:", "chrome-devtools:", and "devtools:" schemes
+    // are internal to the browser; don't want these to be dispatched to other apps.
+    private boolean hasInternalScheme(ExternalNavigationParams params) {
+        if (params.getUrl().startsWith(ContentUrlConstants.ABOUT_URL_SHORT_PREFIX)
+                || params.getUrl().startsWith(UrlConstants.CHROME_URL_SHORT_PREFIX)
+                || params.getUrl().startsWith(UrlConstants.CHROME_NATIVE_URL_SHORT_PREFIX)
+                || params.getUrl().startsWith(UrlConstants.DEVTOOLS_URL_SHORT_PREFIX)
+                || params.getUrl().startsWith(UrlConstants.DEVTOOLS_FALLBACK_URL_SHORT_PREFIX)) {
+            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Navigating to a chrome-internal page");
+            return true;
+        }
+        return false;
+    }
+
+    // The "content:" scheme is disabled in Clank. Do not try to start an activity.
+    private boolean hasContentScheme(ExternalNavigationParams params) {
+        if (!params.getUrl().startsWith(UrlConstants.CONTENT_URL_SHORT_PREFIX)) return false;
+        if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Navigation to content: URL");
+        return true;
+    }
+
+    // Special case - It makes no sense to use an external application for a YouTube
+    // pairing code URL, since these match the current tab with a device (Chromecast
+    // or similar) it is supposed to be controlling. Using a different application
+    // that isn't expecting this (in particular YouTube) doesn't work.
+    private boolean isYoutubePairingCode(ExternalNavigationParams params) {
+        if (params.getUrl().matches(".*youtube\\.com(\\/.*)?\\?(.+&)?pairingCode=[^&].+")) {
+            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: YouTube URL with a pairing code");
+            return true;
+        }
+        return false;
+    }
+
     private @OverrideUrlLoadingResult int shouldOverrideUrlLoadingInternal(
             ExternalNavigationParams params, Intent intent, boolean hasBrowserFallbackUrl,
             String browserFallbackUrl) {
@@ -393,59 +460,19 @@ public class ExternalNavigationHandler {
             return OverrideUrlLoadingResult.NO_OVERRIDE;
         }
 
-        // http://crbug.com/159153: Don't override navigation from a chrome:* url to http or https.
-        // For example when clicking a link in bookmarks or most visited. When navigating from such
-        // a page, there is clear intent to complete the navigation in Chrome.
-        if (params.getReferrerUrl() != null
-                && params.getReferrerUrl().startsWith(UrlConstants.CHROME_URL_PREFIX)
-                && (params.getUrl().startsWith(UrlConstants.HTTP_URL_PREFIX)
-                        || params.getUrl().startsWith(UrlConstants.HTTPS_URL_PREFIX))) {
-            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Link from an internal chrome:// page");
-            return OverrideUrlLoadingResult.NO_OVERRIDE;
-        }
+        if (isLinkFromChromeInternalPage(params)) return OverrideUrlLoadingResult.NO_OVERRIDE;
 
-        if (params.getUrl().startsWith(WTAI_MC_URL_PREFIX)) {
-            // wtai://wp/mc;number
-            // number=string(phone-number)
-            mDelegate.startActivity(new Intent(Intent.ACTION_VIEW,
-                    Uri.parse(WebView.SCHEME_TEL
-                            + params.getUrl().substring(WTAI_MC_URL_PREFIX.length()))), false);
-            if (DEBUG) Log.i(TAG, "OVERRIDE_WITH_EXTERNAL_INTENT wtai:// link handled");
-            RecordUserAction.record("Android.PhoneIntent");
+        if (handleWtaiMcProtocol(params)) {
             return OverrideUrlLoadingResult.OVERRIDE_WITH_EXTERNAL_INTENT;
         }
+        // TODO: handle other WTAI schemes.
+        if (isUnhandledWtaiProtocol(params)) return OverrideUrlLoadingResult.NO_OVERRIDE;
 
-        if (params.getUrl().startsWith(WTAI_URL_PREFIX)) {
-            // TODO: handle other WTAI schemes.
-            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Unsupported wtai:// link");
-            return OverrideUrlLoadingResult.NO_OVERRIDE;
-        }
+        if (hasInternalScheme(params)) return OverrideUrlLoadingResult.NO_OVERRIDE;
 
-        // The "about:", "chrome:", "chrome-native:", "chrome-devtools:", and "devtools:" schemes
-        // are internal to the browser; don't want these to be dispatched to other apps.
-        if (params.getUrl().startsWith(ContentUrlConstants.ABOUT_URL_SHORT_PREFIX)
-                || params.getUrl().startsWith(UrlConstants.CHROME_URL_SHORT_PREFIX)
-                || params.getUrl().startsWith(UrlConstants.CHROME_NATIVE_URL_SHORT_PREFIX)
-                || params.getUrl().startsWith(UrlConstants.DEVTOOLS_URL_SHORT_PREFIX)
-                || params.getUrl().startsWith(UrlConstants.DEVTOOLS_FALLBACK_URL_SHORT_PREFIX)) {
-            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Navigating to a chrome-internal page");
-            return OverrideUrlLoadingResult.NO_OVERRIDE;
-        }
+        if (hasContentScheme(params)) return OverrideUrlLoadingResult.NO_OVERRIDE;
 
-        // The "content:" scheme is disabled in Clank. Do not try to start an activity.
-        if (params.getUrl().startsWith(UrlConstants.CONTENT_URL_SHORT_PREFIX)) {
-            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: Navigation to content: URL");
-            return OverrideUrlLoadingResult.NO_OVERRIDE;
-        }
-
-        // Special case - It makes no sense to use an external application for a YouTube
-        // pairing code URL, since these match the current tab with a device (Chromecast
-        // or similar) it is supposed to be controlling. Using a different application
-        // that isn't expecting this (in particular YouTube) doesn't work.
-        if (params.getUrl().matches(".*youtube\\.com(\\/.*)?\\?(.+&)?pairingCode=[^&].+")) {
-            if (DEBUG) Log.i(TAG, "NO_OVERRIDE: YouTube URL with a pairing code");
-            return OverrideUrlLoadingResult.NO_OVERRIDE;
-        }
+        if (isYoutubePairingCode(params)) return OverrideUrlLoadingResult.NO_OVERRIDE;
 
         // TODO(changwan): check if we need to handle URL even when external intent is off.
         if (CommandLine.getInstance().hasSwitch(