Fix profile avatar downloads.

SignalMessaging/profiles/OWSProfileManager.m

@@ -785,12 +785,9 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
     return nil;
 }
 
-- (void)downloadAvatarForUserProfile:(OWSUserProfile *)userProfileParameter
+- (void)downloadAvatarForUserProfile:(OWSUserProfile *)userProfile
 {
-    OWSAssert(userProfileParameter);
-
-    // Make a local copy.
-    OWSUserProfile *userProfile = [userProfileParameter copy];
+    OWSAssert(userProfile);
 
     dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
         if (userProfile.avatarUrlPath.length < 1) {
@@ -915,14 +912,25 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
             return;
         }
 
+        // If we're transitioning from (no avatar -> no avatar) or from (same avatar -> same avatar),
+        // don't bother updating the avatar.
+        BOOL canSkipAvatarUpdate = ((avatarUrlPath.length == 0 && userProfile.avatarUrlPath.length == 0
+                                        && userProfile.avatarFileName.length == 0)
+            || (avatarUrlPath.length > 0 && userProfile.avatarUrlPath.length > 0 &&
+                   [avatarUrlPath isEqualToString:userProfile.avatarUrlPath] && userProfile.avatarFileName));
+
         NSString *_Nullable profileName =
             [self decryptProfileNameData:profileNameEncrypted profileKey:userProfile.profileKey];
 
+        if (canSkipAvatarUpdate) {
+            [userProfile updateWithProfileName:profileName dbConnection:self.dbConnection completion:nil];
+        } else {
             [userProfile updateWithProfileName:profileName
                                  avatarUrlPath:avatarUrlPath
-                            avatarFileName:userProfile.avatarFileName // use existing file name if already downloaded
+                                avatarFileName:nil
                                   dbConnection:self.dbConnection
                                     completion:nil];
+        }
 
         // If we're updating the profile that corresponds to our local number,
         // update the local profile as well.
@@ -942,7 +950,7 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
                                          completion:nil];
         }
 
-        if (userProfile.avatarUrlPath.length > 0 && userProfile.avatarFileName.length == 0) {
+        if (avatarUrlPath.length > 0) {
             [self downloadAvatarForUserProfile:userProfile];
         }
     });

SignalMessaging/profiles/OWSUserProfile.h

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 #import <SignalServiceKit/TSYapDatabaseObject.h>
@@ -41,6 +41,10 @@ extern NSString *const kLocalProfileUniqueId;
 
 #pragma mark - Update With... Methods
 
+- (void)updateWithProfileName:(nullable NSString *)profileName
+                 dbConnection:(YapDatabaseConnection *)dbConnection
+                   completion:(nullable OWSUserProfileCompletion)completion;
+
 - (void)updateWithProfileName:(nullable NSString *)profileName
                 avatarUrlPath:(nullable NSString *)avatarUrlPath
                avatarFileName:(nullable NSString *)avatarFileName

SignalMessaging/profiles/OWSUserProfile.m

@@ -115,6 +115,8 @@ NSString *const kLocalProfileUniqueId = @"kLocalProfileUniqueId";
             didChange = [_avatarUrlPath isEqualToString:avatarUrlPath];
         }
 
+        _avatarUrlPath = avatarUrlPath;
+
         if (didChange) {
             // If the avatarURL changed, the avatarFileName can't be valid.
             // Clear it.
@@ -137,8 +139,6 @@ NSString *const kLocalProfileUniqueId = @"kLocalProfileUniqueId";
         dbConnection:(YapDatabaseConnection *)dbConnection
           completion:(nullable OWSUserProfileCompletion)completion
 {
-    NSDictionary *beforeSnapshot = self.dictionaryValue;
-
     changeBlock(self);
 
     __block BOOL didChange = YES;
@@ -146,12 +146,16 @@ NSString *const kLocalProfileUniqueId = @"kLocalProfileUniqueId";
         NSString *collection = [[self class] collection];
         OWSUserProfile *_Nullable latestInstance = [transaction objectForKey:self.uniqueId inCollection:collection];
         if (latestInstance) {
+            NSDictionary *beforeSnapshot = latestInstance.dictionaryValue;
+
             changeBlock(latestInstance);
 
             NSDictionary *afterSnapshot = latestInstance.dictionaryValue;
             if ([beforeSnapshot isEqual:afterSnapshot]) {
-                DDLogVerbose(
-                    @"%@ Ignoring redundant update in %s: %@", self.logTag, functionName, self.debugDescription);
+                DDLogVerbose(@"%@ Ignoring redundant update in %s: %@",
+                    self.logTag,
+                    functionName,
+                    self.debugDescription);
                 didChange = NO;
             } else {
                 [latestInstance saveWithTransaction:transaction];
@@ -200,6 +204,18 @@ NSString *const kLocalProfileUniqueId = @"kLocalProfileUniqueId";
     });
 }
 
+- (void)updateWithProfileName:(nullable NSString *)profileName
+                 dbConnection:(YapDatabaseConnection *)dbConnection
+                   completion:(nullable OWSUserProfileCompletion)completion
+{
+    [self applyChanges:^(OWSUserProfile *userProfile) {
+        [userProfile setProfileName:[profileName ows_stripped]];
+    }
+          functionName:__PRETTY_FUNCTION__
+          dbConnection:dbConnection
+            completion:completion];
+}
+
 - (void)updateWithProfileName:(nullable NSString *)profileName
                 avatarUrlPath:(nullable NSString *)avatarUrlPath
                avatarFileName:(nullable NSString *)avatarFileName