[Android] Use Android SDK instead of OpenSSL where possible (#43740)

This PR redirects all RandomNumberGenerator, MD5, Sha1-512, HMAC and AES APIs to use Android SDK instead of OpenSSL.

src/libraries/Native/Unix/CMakeLists.txt

@@ -226,6 +226,7 @@ elseif(CLR_CMAKE_TARGET_TVOS)
 elseif(CLR_CMAKE_TARGET_ANDROID AND NOT CROSS_ROOTFS)
     #add_subdirectory(System.Net.Security.Native) # TODO: reenable
     if (NOT "$ENV{ANDROID_OPENSSL_AAR}" STREQUAL "")
+        set(PREFER_OPENSSL_ANDROID 1)
         add_subdirectory(System.Security.Cryptography.Native)
     endif()
 else()
@@ -237,3 +238,8 @@ endif()
 if(CLR_CMAKE_TARGET_OSX OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     add_subdirectory(System.Security.Cryptography.Native.Apple)
 endif()
+
+# if ANDROID_OPENSSL_AAR is not set - use Android Native Crypto (it's going to replace openssl eventually)
+if(CLR_CMAKE_TARGET_ANDROID AND NOT PREFER_OPENSSL_ANDROID)
+    add_subdirectory(System.Security.Cryptography.Native.Android)
+endif()

src/libraries/Native/Unix/System.Security.Cryptography.Native.Android/CMakeLists.txt

@@ -0,0 +1,32 @@
+project(System.Security.Cryptography.Native.Android C)
+
+add_compile_options(-Wno-gnu-zero-variadic-macro-arguments)
+add_compile_options(-Wno-unused-parameter)
+add_compile_options(-Wno-unused-variable)
+
+set(NATIVECRYPTO_SOURCES
+    android_security.c
+)
+
+add_library(System.Security.Cryptography.Native.Android
+    SHARED
+    ${NATIVECRYPTO_SOURCES}
+    ${VERSION_FILE_PATH}
+)
+
+add_library(System.Security.Cryptography.Native.Android-Static
+    STATIC
+    ${NATIVECRYPTO_SOURCES}
+)
+
+set_target_properties(System.Security.Cryptography.Native.Android-Static PROPERTIES OUTPUT_NAME System.Security.Cryptography.Native.Android CLEAN_DIRECT_OUTPUT 1)
+
+target_link_libraries(System.Security.Cryptography.Native.Android
+    -llog
+)
+
+# TODO: Use "System.Security.Cryptography.Native.Android" name (will require a lot of csproj changes here and there)
+set_target_properties(System.Security.Cryptography.Native.Android PROPERTIES OUTPUT_NAME "System.Security.Cryptography.Native.OpenSsl")
+
+install_with_stripped_symbols (System.Security.Cryptography.Native.Android PROGRAMS .)
+install (TARGETS System.Security.Cryptography.Native.Android-Static DESTINATION .)