[Autofill Assistant] Split DetailsCoordinator into Coordinator + ViewBinder.

Change-Id: I3e9579e7e0fdf3bb90e1a6d806045a6a1207a230
Reviewed-on: https://chromium-review.googlesource.com/c/1430009
Commit-Queue: Jordan Demeulenaere <jdemeulenaere@chromium.org>
Reviewed-by: Stephane Zermatten <szermatt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625361}

chrome/android/java_sources.gni

@@ -155,6 +155,7 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/autofill_assistant/details/AssistantDetails.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/details/AssistantDetailsCoordinator.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/details/AssistantDetailsModel.java",
+  "java/src/org/chromium/chrome/browser/autofill_assistant/details/AssistantDetailsViewBinder.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/header/AnimatedProgressBar.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/header/AssistantHeaderCoordinator.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/header/AssistantHeaderDelegate.java",