Removed investigation CHECK from didCommitNavigation.

This CHECK did not fire. Either because WKNavigation object is nil or
because the assumption from crbug.com/676721 was incorrect.

BUG=676721

Review-Url: https://codereview.chromium.org/2672673002
Cr-Commit-Position: refs/heads/master@{#448058}

ios/web/web_state/ui/crw_web_controller.mm

@@ -4861,16 +4861,6 @@ const NSTimeInterval kSnapshotOverlayTransition = 0.5;
 
 - (void)webView:(WKWebView*)webView
     didCommitNavigation:(WKNavigation*)navigation {
-  // This method will crash if |currentSessionEntry| is null. If this check is
-  // hit it means that |didStartProvisionalNavigation| was called as expected
-  // but it did not call |registerLoadRequest|. TODO(crbug.com/676721): remove
-  // this CHECK once there is at least one crash on this line (which means that
-  // |didStartProvisionalNavigation| did not call |registerLoadRequest| and it
-  // should be fixed.
-  CHECK([self currentSessionEntry] || !navigation ||
-        [_navigationStates stateForNavigation:navigation] ==
-            web::WKNavigationState::STARTED);
-
   [_navigationStates setState:web::WKNavigationState::COMMITTED
                 forNavigation:navigation];
 

ios/web/web_state/ui/crw_wk_navigation_states.h

@@ -54,10 +54,6 @@ enum class WKNavigationState : int {
 // last added navigation. Returns nil if there are no stored navigations.
 - (WKNavigation*)lastAddedNavigation;
 
-// Returns state of the given navigation or WKNavigationState::NONE if
-// navigation does not exist.
-- (web::WKNavigationState)stateForNavigation:(WKNavigation*)navigation;
-
 @end
 
 #endif  // IOS_WEB_WEB_STATE_UI_CRW_WK_NAVIGATION_STATES_H_

ios/web/web_state/ui/crw_wk_navigation_states.mm

@@ -105,9 +105,4 @@
   return result;
 }
 
-- (web::WKNavigationState)stateForNavigation:(WKNavigation*)navigation {
-  CRWWKNavigationsStateRecord* record = [_records objectForKey:navigation];
-  return record.state;
-}
-
 @end

ios/web/web_state/ui/crw_wk_navigation_states_unittest.mm

@@ -41,19 +41,4 @@ TEST_F(CRWWKNavigationStatesTest, LastAddedNavigation) {
   EXPECT_EQ(navigation2_, [states_ lastAddedNavigation]);
 }
 
-// Tests |stateForNavigation:| method.
-TEST_F(CRWWKNavigationStatesTest, StateForNavigation) {
-  [states_ setState:WKNavigationState::REQUESTED forNavigation:navigation1_];
-  EXPECT_EQ(WKNavigationState::REQUESTED,
-            [states_ stateForNavigation:navigation1_]);
-
-  [states_ setState:WKNavigationState::REQUESTED forNavigation:navigation2_];
-  EXPECT_EQ(WKNavigationState::REQUESTED,
-            [states_ stateForNavigation:navigation2_]);
-
-  [states_ setState:WKNavigationState::STARTED forNavigation:navigation1_];
-  EXPECT_EQ(WKNavigationState::STARTED,
-            [states_ stateForNavigation:navigation1_]);
-}
-
 }  // namespace web