Fixing impressions being sent for in-active IAMs

[emawby]

Prior to this PR we would send an IAM impression before validating that we were successfully able to load the html content and display the IAM to the user. This meant that we would still send impressions for cached paused/completed IAMs that would receive a "410 IAM is in-active" error for the loadHTMLContent request. The IAM would not display to the user, but we should not be sending these impressions.

Now we will send IAM impressions in response to the webViewContentFinishedLoading callback which is triggered by the rendering_complete event from the webview's javascript. This guarantees that any errors that occur before displaying the IAM will result in an impression not being sent.

Additionally we will now delete IAMs from the cache that receive the in-active error when loading HTML content so we don't keep trying to display in-active IAMs.

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This change is 

[jkasten2]

Reviewed 7 of 7 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @emawby and @Jeasmine)

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iOS_SDK/OneSignalSDK/Source/OSInAppMessageViewController.m, line 269 at r1 (raw file):

- (void)encounteredErrorLoadingMessageContent:(NSError * _Nullable)error {
    let message = [NSString stringWithFormat:@"An error occurred while attempting to load message content: %@", error.description ?: @"Unknown Error"];
    if (error.code == 410 || [error.description containsString:@"In-App Message is not active"]) {

Shouldn't code against a human readable message as it could change. I word remove the the description check.
Also we should check for 404.

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iOS_SDK/OneSignalSDK/UnitTests/UnitTestCommonMethods.m, line 155 at r1 (raw file):

 This will allow more time for chained async methods to complete
 */
+ (void)runLongBackgroundThreads {

This new selector shares a lot of with runBackgroundThreads. Can the code between the be shared?

[emawby]

Reviewable status: 5 of 12 files reviewed, 2 unresolved discussions (waiting on @Jeasmine and @jkasten2)

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iOS_SDK/OneSignalSDK/Source/OSInAppMessageViewController.m, line 269 at r1 (raw file):

Previously, jkasten2 (Josh Kasten) wrote…

Shouldn't code against a human readable message as it could change. I word remove the the description check.
Also we should check for 404.

Done.

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iOS_SDK/OneSignalSDK/UnitTests/UnitTestCommonMethods.m, line 155 at r1 (raw file):

Previously, jkasten2 (Josh Kasten) wrote…

This new selector shares a lot of with runBackgroundThreads. Can the code between the be shared?

Done.

[jkasten2]

Reviewed 7 of 7 files at r2.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @Jeasmine and @jkasten2)

[jkasten2]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @Jeasmine)