[ToolbarMVC] Fix load progress for same-document nav

The LoadProgress MVC refactoring inadvertently dropped a check against
starting load progress for same-doc navs; this patch restores that check.

Bug: 1058778
Change-Id: I17087cdefe9ecadb37e6ca84cc75839a7ccee59c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2088833
Commit-Queue: Patrick Noland <pnoland@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747431}

chrome/android/java/src/org/chromium/chrome/browser/toolbar/load_progress/LoadProgressMediator.java

@@ -32,7 +32,7 @@ public class LoadProgressMediator {
         mTabObserver = new ActivityTabProvider.ActivityTabTabObserver(activityTabProvider) {
             @Override
             public void onDidStartNavigation(Tab tab, NavigationHandle navigation) {
-                if (!navigation.isInMainFrame()) {
+                if (navigation.isSameDocument() || !navigation.isInMainFrame()) {
                     return;
                 }
 

chrome/android/junit/src/org/chromium/chrome/browser/toolbar/load_progress/LoadProgressMediatorTest.java

@@ -185,4 +185,23 @@ public class LoadProgressMediatorTest {
         assertEquals(mModel.get(LoadProgressProperties.COMPLETION_STATE),
                 CompletionState.FINISHED_DO_ANIMATE);
     }
+
+    @Test
+    public void testSameDocumentLoad_afterFinishedLoading() {
+        assertEquals(mModel.get(LoadProgressProperties.COMPLETION_STATE),
+                CompletionState.FINISHED_DONT_ANIMATE);
+
+        NavigationHandle navigation = new NavigationHandle(0, URL_1, true, false, false);
+        mTabObserver.onDidStartNavigation(mTab, navigation);
+        mTabObserver.onLoadProgressChanged(mTab, 1.0f);
+        assertEquals(mModel.get(LoadProgressProperties.PROGRESS), 1.0f, MathUtils.EPSILON);
+        assertEquals(mModel.get(LoadProgressProperties.COMPLETION_STATE),
+                CompletionState.FINISHED_DO_ANIMATE);
+        NavigationHandle sameDocNav = new NavigationHandle(0, URL_1, true, true, false);
+        mTabObserver.onDidStartNavigation(mTab, sameDocNav);
+
+        assertEquals(mModel.get(LoadProgressProperties.PROGRESS), 1.0f, MathUtils.EPSILON);
+        assertEquals(mModel.get(LoadProgressProperties.COMPLETION_STATE),
+                CompletionState.FINISHED_DO_ANIMATE);
+    }
 }