Replacing #781 - replaced all the remaining `dispatch_main_sync_safe` with `dispatch_main_async_safe`, so we no longer `dispatch_sync` on the main queue that can create issues.

SDWebImage/SDWebImageCompat.h

@@ -99,13 +99,6 @@ typedef void(^SDWebImageNoParamsBlock)();
 
 extern NSString *const SDWebImageErrorDomain;
 
-#define dispatch_main_sync_safe(block)\
-    if ([NSThread isMainThread]) {\
-        block();\
-    } else {\
-        dispatch_sync(dispatch_get_main_queue(), block);\
-    }
-
 #define dispatch_main_async_safe(block)\
     if (strcmp(dispatch_queue_get_label(DISPATCH_CURRENT_QUEUE_LABEL), dispatch_queue_get_label(dispatch_get_main_queue())) == 0) {\
         block();\

SDWebImage/SDWebImageDownloaderOperation.m

@@ -372,7 +372,7 @@ didReceiveResponse:(NSURLResponse *)response
                     image = scaledImage;
                 }
                 CGImageRelease(partialImageRef);
-                dispatch_main_sync_safe(^{
+                dispatch_main_async_safe(^{
                     for (SDWebImageDownloaderCompletedBlock completedBlock in [self callbacksForKey:kCompletedCallbackKey]) {
                         completedBlock(image, nil, nil, NO);
                     }

SDWebImage/SDWebImageManager.m

@@ -131,7 +131,7 @@
     }
 
     if (url.absoluteString.length == 0 || (!(options & SDWebImageRetryFailed) && isFailedUrl)) {
-        dispatch_main_sync_safe(^{
+        dispatch_main_async_safe(^{
             NSError *error = [NSError errorWithDomain:NSURLErrorDomain code:NSURLErrorFileDoesNotExist userInfo:nil];
             completedBlock(nil, nil, error, SDImageCacheTypeNone, YES, url);
         });
@@ -154,7 +154,7 @@
 
         if ((!cachedImage || options & SDWebImageRefreshCached) && (![self.delegate respondsToSelector:@selector(imageManager:shouldDownloadImageForURL:)] || [self.delegate imageManager:self shouldDownloadImageForURL:url])) {
             if (cachedImage && options & SDWebImageRefreshCached) {
-                dispatch_main_sync_safe(^{
+                dispatch_main_async_safe(^{
                     // If image was found in the cache but SDWebImageRefreshCached is provided, notify about the cached image
                     // AND try to re-download it in order to let a chance to NSURLCache to refresh it from server.
                     completedBlock(cachedImage, cachedData, nil, cacheType, YES, url);
@@ -183,7 +183,7 @@
                     // See #699 for more details
                     // if we would call the completedBlock, there could be a race condition between this block and another completedBlock for the same object, so if this one is called second, we will overwrite the new data
                 } else if (error) {
-                    dispatch_main_sync_safe(^{
+                    dispatch_main_async_safe(^{
                         if (strongOperation && !strongOperation.isCancelled) {
                             completedBlock(nil, nil, error, SDImageCacheTypeNone, finished, url);
                         }
@@ -222,7 +222,7 @@
                                 [self.imageCache storeImage:transformedImage imageData:(imageWasTransformed ? nil : downloadedData) forKey:key toDisk:cacheOnDisk completion:nil];
                             }
 
-                            dispatch_main_sync_safe(^{
+                            dispatch_main_async_safe(^{
                                 if (strongOperation && !strongOperation.isCancelled) {
                                     completedBlock(transformedImage, downloadedData, nil, SDImageCacheTypeNone, finished, url);
                                 }
@@ -233,7 +233,7 @@
                             [self.imageCache storeImage:downloadedImage imageData:downloadedData forKey:key toDisk:cacheOnDisk completion:nil];
                         }
 
-                        dispatch_main_sync_safe(^{
+                        dispatch_main_async_safe(^{
                             if (strongOperation && !strongOperation.isCancelled) {
                                 completedBlock(downloadedImage, downloadedData, nil, SDImageCacheTypeNone, finished, url);
                             }
@@ -260,7 +260,7 @@
                 }
             };
         } else if (cachedImage) {
-            dispatch_main_sync_safe(^{
+            dispatch_main_async_safe(^{
                 __strong __typeof(weakOperation) strongOperation = weakOperation;
                 if (strongOperation && !strongOperation.isCancelled) {
                     completedBlock(cachedImage, cachedData, nil, cacheType, YES, url);
@@ -271,7 +271,7 @@
             }
         } else {
             // Image not in cache and download disallowed by delegate
-            dispatch_main_sync_safe(^{
+            dispatch_main_async_safe(^{
                 __strong __typeof(weakOperation) strongOperation = weakOperation;
                 if (strongOperation && !weakOperation.isCancelled) {
                     completedBlock(nil, nil, nil, SDImageCacheTypeNone, YES, url);

SDWebImage/UIImageView+WebCache.m

@@ -78,7 +78,7 @@
     for (NSURL *logoImageURL in arrayOfURLs) {
         id <SDWebImageOperation> operation = [SDWebImageManager.sharedManager loadImageWithURL:logoImageURL options:0 progress:nil completed:^(UIImage *image, NSData *data, NSError *error, SDImageCacheType cacheType, BOOL finished, NSURL *imageURL) {
             if (!wself) return;
-            dispatch_main_sync_safe(^{
+            dispatch_main_async_safe(^{
                 __strong UIImageView *sself = wself;
                 [sself stopAnimating];
                 if (sself && image) {

SDWebImage/UIView+WebCache.m

@@ -57,7 +57,7 @@ static char TAG_ACTIVITY_SHOW;
             if (!sself) {
                 return;
             }
-            dispatch_main_sync_safe(^{
+            dispatch_main_async_safe(^{
                 if (!sself) {
                     return;
                 }