Remove usage of Tab's |url| property from TabUsageRecorder.

ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm

Index: ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm
diff --git a/ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm b/ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm
index ca0817bb3b7d0c7201b6f0f7c9e7959367255ad4..31672db7ce4483cc2514fefd37b40d67a4a9db8a 100644
--- a/ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm
+++ b/ios/chrome/browser/metrics/tab_usage_recorder_unittest.mm
@@ -4,6 +4,7 @@
 
 #include <memory>
 
+#include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram_samples.h"
 #include "base/stl_util.h"
@@ -13,6 +14,8 @@
 #import "ios/chrome/browser/metrics/tab_usage_recorder_delegate.h"
 #import "ios/chrome/browser/tabs/tab.h"
 #include "ios/testing/ocmock_complex_type_helper.h"
+#import "ios/web/public/test/fakes/test_navigation_manager.h"
+#import "ios/web/public/test/fakes/test_web_state.h"
 #include "ios/web/public/test/test_web_thread.h"
 #import "ios/web/web_state/ui/crw_web_controller.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -25,9 +28,16 @@
 
 @interface TURTestTabMock : OCMockComplexTypeHelper {
   GURL _url;
+  GURL _lastCommittedURL;
+  GURL _visibleURL;
+  web::TestWebState _webState;
 }
 
 @property(nonatomic, assign) const GURL& url;
+@property(nonatomic, assign) const GURL& lastCommittedURL;
+@property(nonatomic, assign) const GURL& visibleURL;
+@property(nonatomic, readonly) web::WebState* webState;
+
 @end
 
 @implementation TURTestTabMock
@@ -37,6 +47,25 @@ @implementation TURTestTabMock
 - (void)setUrl:(const GURL&)url {
   _url = url;
 }
+- (const GURL&)lastCommittedURL {
+  return _lastCommittedURL;
+}
+- (void)setLastCommittedURL:(const GURL&)lastCommittedURL {
+  _lastCommittedURL = lastCommittedURL;
+}
+- (const GURL&)visibleURL {
+  return _visibleURL;
+}
+- (void)setVisibleURL:(const GURL&)visibleURL {
+  _visibleURL = visibleURL;
+}
+- (web::WebState*)webState {
+  if (!_webState.GetNavigationManager()) {
+    _webState.SetNavigationManager(
+        base::MakeUnique<web::TestNavigationManager>());
+  }
+  return &_webState;
+}
 @end
 
 // A mock TabUsageRecorderDelegate which allows the unit tests to control
@@ -106,6 +135,8 @@ id MockTab(bool inMemory) {
     [[[tab_mock stub] andReturn:web_controller_mock] webController];
     [[[tab_mock stub] andReturnBool:false] isPrerenderTab];
     [tab_mock setUrl:webUrl_];
+    [tab_mock setLastCommittedURL:webUrl_];
+    [tab_mock setVisibleURL:webUrl_];
     [[[web_controller_mock stub] andReturnBool:inMemory] isViewAlive];
     [[web_controller_mock stub] removeObserver:OCMOCK_ANY];
     return tab_mock;
@@ -173,7 +204,11 @@ id MockTab(bool inMemory) {
   id tab_mock_a = MockTab(true);
   id tab_mock_b = MockTab(false);
   [tab_mock_a setUrl:nativeUrl_];
+  [tab_mock_a setLastCommittedURL:nativeUrl_];
+  [tab_mock_a setVisibleURL:nativeUrl_];
   [tab_mock_b setUrl:nativeUrl_];
+  [tab_mock_b setLastCommittedURL:nativeUrl_];
+  [tab_mock_b setVisibleURL:nativeUrl_];
 
   // Call reload an arbitrary number of times.
   const int kNumReloads = 4;