Build Mono WebAssembly runtime and BCLs

We force using Emscripten 1.38.47 as there is a regression in 1.38.48
and 1.39.x which makes the generation of our .wasm file fail.

Up until now we used the desktop BCL (compiled with desktop Mono)
for both desktop and Android, but that does not work for WebAssembly
(and we suspect Android issues related to it).

So we now build the Android and WebAssembly BCLs in the relevant
containers, which are later copied in the templates directory to
include on export. We already have the desktop BCL from the regular
build.

Dockerfile.android

@@ -17,14 +17,17 @@ ENV ANDROID_HOME=/root/sdk/
 ENV ANDROID_NDK_ROOT=/root/sdk/ndk-bundle/
 
 RUN git clone https://github.com/mono/mono --branch mono-${mono_version} --single-branch && \
-    cd mono && git submodule update --init && \
-    patch -p1 < /root/files/patches/fix-mono-android-tkill.diff && \
-    cd .. && \
+    cd mono && git submodule update --init && cd .. && \
+    export MONO_SOURCE_ROOT=/root/mono && \
     git clone https://github.com/godotengine/godot-mono-builds && \
     cd godot-mono-builds && \
-    git checkout 9efec19e6b61fdc7201067cff4dd5b741399ae31 && \
-    ./build_mono_android.py configure --target=all --mono-sources=/root/mono && \
-    ./build_mono_android.py make --target=all --mono-sources=/root/mono && \
+    git checkout bd129da22b8b9c96f3e8b07af348cc5fb61504bf && \
+    python3 patch_mono.py && \
+    python3 android.py configure --target=all-runtime && \
+    python3 android.py make --target=all-runtime && \
+    cd /root/mono && git clean -fdx && NOCONFIGURE=1 ./autogen.sh && \
+    cd /root/godot-mono-builds && \
+    python3 bcl.py make --product=android && \
     cd .. && \
     rm -rf /root/mono /root/godot-mono-builds