[Unity][Android] Set and track consent text in SigninFragmentBase

This CL extracts ConsentTextTracker from AccountSigninView and
implements consent recording in SigninFragmentBase by using
ConsentTextTracker.

Bug: 814728
Change-Id: I7c699e63bea7a2c61244e72956d4774d46d79556
Reviewed-on: https://chromium-review.googlesource.com/964841
Reviewed-by: Bernhard Bauer <[email protected]>
Commit-Queue: Boris Sazonov <[email protected]>
Cr-Commit-Position: refs/heads/master@{#544350}
diff --git a/chrome/android/java_sources.gni b/chrome/android/java_sources.gni
index 48017979..7756401 100644
--- a/chrome/android/java_sources.gni
+++ b/chrome/android/java_sources.gni
@@ -1106,6 +1106,7 @@
   "java/src/org/chromium/chrome/browser/signin/ConfirmManagedSyncDataDialog.java",
   "java/src/org/chromium/chrome/browser/signin/ConfirmSyncDataStateMachine.java",
   "java/src/org/chromium/chrome/browser/signin/ConfirmSyncDataStateMachineDelegate.java",
+  "java/src/org/chromium/chrome/browser/signin/ConsentTextTracker.java",
   "java/src/org/chromium/chrome/browser/signin/DisplayableProfileData.java",
   "java/src/org/chromium/chrome/browser/signin/GoogleActivityController.java",
   "java/src/org/chromium/chrome/browser/signin/OAuth2TokenService.java",