ios: automagically download a bitcode WebRTC build if needed

ios/scripts/bitcode.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+# This script will download a bitcode build of the WebRTC framework, if needed.
+
+if [[ ! "$CONFIGURATION" = "Debug" ]]; then
+    RN_WEBRTC="$SRCROOT/../../node_modules/react-native-webrtc"
+
+    if otool -arch arm64 -l $RN_WEBRTC/ios/WebRTC.framework/WebRTC | grep -q LLVM; then
+        echo "WebRTC framework has bitcode"
+    else
+        echo "WebRTC framework has NO bitcode"
+        $RN_WEBRTC/tools/downloadBitcode.sh
+    fi
+fi
+