Merge pull request #982 from OneSignal/feature/IAM_transparent_background

Enable Transparent IAM backgrounds

Author: emawby

iOS_SDK/OneSignalSDK/Source/OSInAppMessageView.m

@@ -111,7 +111,8 @@ - (void)setupWebviewWithMessageHandler:(id<WKScriptMessageHandler>)handler {
 
     // Setup WebView, delegates, and disable scrolling inside of the WebView
     self.webView = [[WKWebView alloc] initWithFrame:mainBounds configuration:configuration];
-    
+    self.webView.backgroundColor = [UIColor clearColor];
+    self.webView.opaque = NO;
     [self addSubview:self.webView];
 
     [self layoutIfNeeded];