[ios] Refactor CrashRestoreHelper for multi-window and multi-profile

The code to deal with multi-window enabled/disabled was duplicated in
CrashRestoreHelper where calling the multi-window enabled code with a
session with an empty name was the same as calling code for single
window. Refactor the code to avoid the duplication.

Change the backup directory used for the saved session when restore
is in progress as the single directory approach would not work with
multi-profile.

Bug: 1165798
Change-Id: Ifa6efe051999b77688a8a6ffdb8b9ed3b185e60e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2632677
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Stepan Khapugin <stkhapugin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845174}

ios/chrome/app/main_controller.mm

@@ -485,16 +485,13 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
   // browser state.
   BOOL needRestoration = NO;
   if (isPostCrashLaunch) {
-    if (IsMultiwindowSupported()) {
-      NSSet<NSString*>* sessions =
-          [[PreviousSessionInfo sharedInstance] connectedSceneSessionsIDs];
-      needRestoration =
-          [CrashRestoreHelper moveAsideSessions:sessions
-                                forBrowserState:chromeBrowserState];
-    } else {
-      needRestoration = [CrashRestoreHelper
-          moveAsideSessionInformationForBrowserState:chromeBrowserState];
-    }
+    NSSet<NSString*>* sessions =
+        IsMultiwindowSupported()
+            ? [[PreviousSessionInfo sharedInstance] connectedSceneSessionsIDs]
+            : [NSSet setWithArray:@[ @"" ]];
+
+    needRestoration = [CrashRestoreHelper moveAsideSessions:sessions
+                                            forBrowserState:chromeBrowserState];
   }
   if (!IsMultipleScenesSupported() && IsMultiwindowSupported()) {
     NSSet<NSString*>* previousSessions =

ios/chrome/browser/crash_report/crash_restore_helper.h

@@ -16,7 +16,8 @@ class ChromeBrowserState;
 - (instancetype)initWithBrowser:(Browser*)browser;
 
 // Returns YES if a backup file for sessionID can be found on disk.
-+ (BOOL)isBackedUpSessionID:(NSString*)sessionID;
++ (BOOL)isBackedUpSessionID:(NSString*)sessionID
+               browserState:(ChromeBrowserState*)browserState;
 
 // Saves the session information stored on disk for sessions with |sessionIDs|
 // in temporary files and will then delete those from their default location.
@@ -29,17 +30,18 @@ class ChromeBrowserState;
 + (BOOL)moveAsideSessions:(NSSet<NSString*>*)sessionIDs
           forBrowserState:(ChromeBrowserState*)browserState;
 
-// Move the session information for Legacy non multiwindow supported OS.
-// This method deletes the session from its default location, while
-// allowing restoring it back later.
-// Returns |YES| if the delettion and backup was successful.
-+ (BOOL)moveAsideSessionInformationForBrowserState:
-    (ChromeBrowserState*)browserState;
-
 // Shows an infobar on the currently active tab of the browser. This infobar
 // lets the user restore its session after a crash.
 - (void)showRestorePrompt;
 
 @end
 
+@interface CrashRestoreHelper (Testing)
+
+// Returns the path for back of session |sessionID| relative in |directory|.
++ (NSString*)backupPathForSessionID:(NSString*)sessionID
+                          directory:(NSString*)directory;
+
+@end
+
 #endif  // IOS_CHROME_BROWSER_CRASH_REPORT_CRASH_RESTORE_HELPER_H_

ios/chrome/browser/crash_report/crash_restore_helper_unittest.mm

@@ -28,10 +28,6 @@
 
 using testing::Return;
 
-@interface CrashRestoreHelper (Test)
-+ (NSString*)backupPathForSessionID:(NSString*)sessionID;
-@end
-
 namespace {
 
 class CrashRestoreHelperTest : public PlatformTest {
@@ -55,13 +51,14 @@ class CrashRestoreHelperTest : public PlatformTest {
         chrome_browser_state_.get(),
         off_the_record_chrome_browser_state_,
     };
-    NSString* backup_path =
-        [CrashRestoreHelper backupPathForSessionID:session_id];
-    [file_manager removeItemAtPath:backup_path error:nil];
     NSData* data = [NSData dataWithBytes:"hello" length:5];
     for (size_t index = 0; index < base::size(browser_states); ++index) {
       NSString* state_path = base::SysUTF8ToNSString(
           browser_states[index]->GetStatePath().value());
+      NSString* backup_path =
+          [CrashRestoreHelper backupPathForSessionID:session_id
+                                           directory:state_path];
+      [file_manager removeItemAtPath:backup_path error:nil];
       NSString* session_path =
           [SessionServiceIOS sessionPathForSessionID:session_id
                                            directory:state_path];
@@ -103,10 +100,14 @@ class CrashRestoreHelperTest : public PlatformTest {
   // Returns |true| if the session with |session_id| was backed up correctly,
   // and deletes the backup file. if |session_id| is nil, the default backup
   // session location is used.
-  bool CheckAndDeleteSessionBackedUp(NSString* session_id) {
+  bool CheckAndDeleteSessionBackedUp(NSString* session_id,
+                                     ChromeBrowserState* browser_state) {
     NSFileManager* file_manager = [NSFileManager defaultManager];
-    NSString* backup_path =
-        [CrashRestoreHelper backupPathForSessionID:session_id];
+    NSString* backup_path = [CrashRestoreHelper
+        backupPathForSessionID:session_id
+                     directory:base::SysUTF8ToNSString(
+                                   browser_state->GetStatePath()
+                                       .AsUTF8Unsafe())];
     if (![file_manager fileExistsAtPath:backup_path])
       return false;
     [file_manager removeItemAtPath:backup_path error:nil];
@@ -123,14 +124,12 @@ class CrashRestoreHelperTest : public PlatformTest {
 // Tests that moving session work correctly when multiple windows are not
 // supported.
 TEST_F(CrashRestoreHelperTest, MoveAsideSingleSession) {
-  // This test is only enabled when multi-window is disabled.
-  if (IsMultiwindowSupported())
-    return;
   ASSERT_TRUE(CreateSession(nil));
-  [CrashRestoreHelper
-      moveAsideSessionInformationForBrowserState:chrome_browser_state_.get()];
+  [CrashRestoreHelper moveAsideSessions:[NSSet setWithArray:@[ @"" ]]
+                        forBrowserState:chrome_browser_state_.get()];
   EXPECT_TRUE(IsSessionErased(nil));
-  EXPECT_EQ(YES, CheckAndDeleteSessionBackedUp(nil));
+  EXPECT_EQ(YES,
+            CheckAndDeleteSessionBackedUp(nil, chrome_browser_state_.get()));
 }
 
 // Tests that moving session work correctly when multiple windows are supported.
@@ -145,7 +144,8 @@ TEST_F(CrashRestoreHelperTest, MoveAsideMultipleSessions) {
                         forBrowserState:chrome_browser_state_.get()];
   for (NSString* session_id in session_ids) {
     EXPECT_TRUE(IsSessionErased(session_id));
-    EXPECT_EQ(YES, CheckAndDeleteSessionBackedUp(session_id));
+    EXPECT_EQ(YES, CheckAndDeleteSessionBackedUp(session_id,
+                                                 chrome_browser_state_.get()));
   }
 }
 

ios/chrome/browser/sessions/session_service_ios.mm

@@ -215,7 +215,7 @@ NSString* const kSessionFileName =
 
 + (NSString*)sessionPathForSessionID:(NSString*)sessionID
                            directory:(NSString*)directory {
-  if (!sessionID)
+  if (!sessionID.length)
     return [[self class] sessionPathForDirectory:directory];
   return [NSString pathWithComponents:@[
     directory, kSessionDirectory, sessionID, kSessionFileName

ios/chrome/browser/ui/main/scene_controller.mm

@@ -677,12 +677,13 @@ const char kMultiWindowOpenInNewWindowHistogram[] =
   // Only create the restoration helper if the session with the current session
   // id was backed up successfully.
   if (self.sceneState.appState.sessionRestorationRequired) {
+    Browser* mainBrowser = self.mainInterface.browser;
     if (!IsMultiwindowSupported() ||
         [CrashRestoreHelper
-            isBackedUpSessionID:self.sceneState.sceneSessionID]) {
+            isBackedUpSessionID:self.sceneState.sceneSessionID
+                   browserState:mainBrowser->GetBrowserState()]) {
       self.sceneState.appState.startupInformation.restoreHelper =
-          [[CrashRestoreHelper alloc]
-              initWithBrowser:self.mainInterface.browser];
+          [[CrashRestoreHelper alloc] initWithBrowser:mainBrowser];
     }
   }