Fix crashes in AutofillControllerTest.KeyValueFocusChange

The test is likely crashing because of out of bounds exception. Using
ASSERT_EQ instead of EXPECT_EQ should stop the test before accessing
invalid index.

This CL does not fix the failing test, it just replaces crash with
a graceful failure.

Bug: 1060251
Change-Id: I214a4aae84274f5c191ad665c906743cc3f856d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2094709
Commit-Queue: Olivier Robin <olivierrobin@chromium.org>
Auto-Submit: Eugene But <eugenebut@chromium.org>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749079}

ios/chrome/browser/autofill/autofill_controller_unittest.mm

@@ -601,7 +601,7 @@ TEST_F(AutofillControllerTest, KeyValueFocusChange) {
   // Focus the dummy field and confirm no suggestions are presented.
   ExecuteJavaScript(@"document.forms[0].dummy.focus()");
   WaitForSuggestionRetrieval(/*wait_for_trigger=*/YES);
-  EXPECT_EQ(0U, [suggestion_controller() suggestions].count);
+  ASSERT_EQ(0U, [suggestion_controller() suggestions].count);
 
   // Enter 'B' in the dummy field and confirm no suggestions are presented.
   ExecuteJavaScript(@"event = document.createEvent('TextEvent');");
@@ -609,7 +609,7 @@ TEST_F(AutofillControllerTest, KeyValueFocusChange) {
       @"event.initTextEvent('textInput', true, true, window, 'B');");
   ExecuteJavaScript(@"document.forms[0].dummy.dispatchEvent(event);");
   WaitForSuggestionRetrieval(/*wait_for_trigger=*/YES);
-  EXPECT_EQ(0U, [suggestion_controller() suggestions].count);
+  ASSERT_EQ(0U, [suggestion_controller() suggestions].count);
 
   // Enter 'B' in the greeting field and confirm that one suggestion ("Bonjour")
   // is presented.
@@ -620,7 +620,7 @@ TEST_F(AutofillControllerTest, KeyValueFocusChange) {
       @"event.initTextEvent('textInput', true, true, window, 'B');");
   ExecuteJavaScript(@"document.forms[0].greeting.dispatchEvent(event);");
   WaitForSuggestionRetrieval(/*wait_for_trigger=*/YES);
-  EXPECT_EQ(1U, [suggestion_controller() suggestions].count);
+  ASSERT_EQ(1U, [suggestion_controller() suggestions].count);
   FormSuggestion* suggestion = [suggestion_controller() suggestions][0];
   EXPECT_NSEQ(@"Bonjour", suggestion.value);
 }