[Autofill Assistant] Remove navigation feature

The condition has shown to be stable enough that the bailout can be
removed.

Bug: b/159309621
Change-Id: I4d66174ac0fd2c117d31aa81303b2d2ee1e7cf84
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2414179Reviewed-by: Mathias Carlen <mcarlen@chromium.org>
Commit-Queue: Sandro Maggi <sandromaggi@google.com>
Cr-Commit-Position: refs/heads/master@{#808805}

components/autofill_assistant/browser/controller.cc

@@ -1843,8 +1843,6 @@ void Controller::DidStartNavigation(
     return;
   }
 
-  if (base::FeatureList::IsEnabled(
-          features::kAutofillAssistantBreakOnRunningNavigation)) {
   // When in RUNNING state, all renderer initiated navigation is allowed,
   // user initiated navigation will cause an error.
   if (state_ == AutofillAssistantState::RUNNING &&
@@ -1854,7 +1852,6 @@ void Controller::DidStartNavigation(
                   Metrics::DropOutReason::NAVIGATION_WHILE_RUNNING);
     return;
   }
-  }
 
   // Note that BROWSE state end conditions are in DidFinishNavigation, in order
   // to be able to properly evaluate the committed url.

components/autofill_assistant/browser/features.cc

@@ -12,14 +12,6 @@ namespace features {
 const base::Feature kAutofillAssistant{"AutofillAssistant",
                                        base::FEATURE_ENABLED_BY_DEFAULT};
 
-// Guard for the end condition when a non-renderer-initiated navigation occurs
-// while the AutofillAssistant is in RUNNING state.
-// TODO(b/159309621): Remove this if the end condition shows no unwanted side
-// effects.
-const base::Feature kAutofillAssistantBreakOnRunningNavigation{
-    "AutofillAssistantBreakOnRunningNavigation",
-    base::FEATURE_ENABLED_BY_DEFAULT};
-
 // Controls whether to enable Assistant Autofill in a normal Chrome tab.
 const base::Feature kAutofillAssistantChromeEntry{
     "AutofillAssistantChromeEntry", base::FEATURE_ENABLED_BY_DEFAULT};

components/autofill_assistant/browser/features.h

@@ -14,7 +14,6 @@ namespace features {
 
 // All features in alphabetical order.
 extern const base::Feature kAutofillAssistant;
-extern const base::Feature kAutofillAssistantBreakOnRunningNavigation;
 extern const base::Feature kAutofillAssistantChromeEntry;
 extern const base::Feature kAutofillAssistantDirectActions;