[iOS] Log when existing URL is being opened

The idea is to log when the user is opening a URL (from another app)
which is already opened in the app.
Having this metrics will allow us to know if it is impactful to handle
this special case.

Bug: 1014964
Change-Id: I94c7b7810eb66c81ec310057d1b4b991dad55ab7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1869412Reviewed-by: Nik Bhagat <nikunjb@chromium.org>
Reviewed-by: Stepan Khapugin <stkhapugin@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710130}

ios/chrome/app/application_delegate/mock_tab_opener.mm

@@ -55,4 +55,8 @@
   return NO;
 }
 
+- (BOOL)URLIsOpenedInRegularMode:(const GURL&)URL {
+  return NO;
+}
+
 @end

ios/chrome/app/application_delegate/tab_opening.h

@@ -11,6 +11,7 @@
 #include "ui/base/page_transition_types.h"
 
 @class AppState;
+class GURL;
 @class TabModel;
 @protocol StartupInformation;
 struct UrlLoadParams;
@@ -52,6 +53,9 @@ enum class ApplicationModeForTabOpening { NORMAL, INCOGNITO, CURRENT };
 - (BOOL)shouldCompletePaymentRequestOnCurrentTab:
     (id<StartupInformation>)startupInformation;
 
+// Whether the |URL| is already opened, in regular mode.
+- (BOOL)URLIsOpenedInRegularMode:(const GURL&)URL;
+
 @end
 
 #endif  // IOS_CHROME_APP_APPLICATION_DELEGATE_TAB_OPENING_H_

ios/chrome/app/application_delegate/url_opener.mm

@@ -89,6 +89,11 @@ const char* const kUMAMobileSessionStartFromAppsHistogram =
       if (callerApp == CALLER_APP_GOOGLE_CHROME)
         targetMode = ApplicationModeForTabOpening::CURRENT;
 
+      if (![params launchInIncognito] &&
+          [tabOpener URLIsOpenedInRegularMode:urlLoadParams.web_params.url]) {
+        // Record metric.
+      }
+
       [tabOpener
           dismissModalsAndOpenSelectedTabInMode:targetMode
                               withUrlLoadParams:urlLoadParams

ios/chrome/app/application_delegate/user_activity_handler.mm

@@ -177,6 +177,10 @@ NSString* const kShortcutQRScanner = @"OpenQRScanner";
             ? ApplicationModeForTabOpening::INCOGNITO
             : ApplicationModeForTabOpening::NORMAL;
     UrlLoadParams params = UrlLoadParams::InNewTab(webpageGURL);
+    if (![[startupInformation startupParameters] launchInIncognito] &&
+        [tabOpener URLIsOpenedInRegularMode:webpageGURL]) {
+      // Record metric.
+    }
     [tabOpener dismissModalsAndOpenSelectedTabInMode:targetMode
                                    withUrlLoadParams:params
                                       dismissOmnibox:YES
@@ -313,6 +317,11 @@ NSString* const kShortcutQRScanner = @"OpenQRScanner";
       params.web_params.url = result;
     }
 
+    if (![[startupInformation startupParameters] launchInIncognito] &&
+        [tabOpener URLIsOpenedInRegularMode:params.web_params.url]) {
+      // Record metric.
+    }
+
     [tabOpener dismissModalsAndOpenSelectedTabInMode:targetMode
                                    withUrlLoadParams:params
                                       dismissOmnibox:[[startupInformation

ios/chrome/app/main_controller.mm

@@ -2186,6 +2186,12 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
   return YES;
 }
 
+- (BOOL)URLIsOpenedInRegularMode:(const GURL&)URL {
+  WebStateList* webStateList = self.mainTabModel.webStateList;
+  return webStateList && webStateList->GetIndexOfWebStateWithURL(URL) !=
+                             WebStateList::kInvalidIndex;
+}
+
 #pragma mark - SettingsNavigationControllerDelegate
 
 - (void)closeSettings {