kodev: Add $ANDROID_ARCH to enable x86 build (#3353)

You'll still have to call it with `ANDROID_ARCH=x86 ./kodev build/release/run android`.

Don't forget to `./mk-luajit.sh clean` in luajit-launcher when changing architectures.

* Bump android-luajit-launcher
  This includes the fix for Android 8. Fixes #3126.
* Bump base

kodev

@@ -3,6 +3,17 @@
 CURDIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 VERSION=$(git describe HEAD)
 
+# Default Android build to arm.
+ANDROID_ARCH=${ANDROID_ARCH:-arm}
+if [ -z "${ANDROID_FULL_ARCH+x}" ]; then
+    if [ "$ANDROID_ARCH" = arm ]; then
+        ANDROID_FULL_ARCH_APK="${ANDROID_FULL_ARCH_APK:-arm-linux-androideabi}"
+    elif [ "$ANDROID_ARCH" = x86 ]; then
+        ANDROID_FULL_ARCH_APK="${ANDROID_FULL_ARCH_APK:-i686-linux-android}"
+    else
+        ANDROID_FULL_ARCH_APK="${ANDROID_ARCH}"
+    fi
+fi
 # Default to Android 4.0+; required for NDK 15 but with a custom NDK the strict minimum is 9.
 NDKABI=${NDKABI:-14}
 export NDKABI
@@ -165,7 +176,7 @@ ${SUPPORTED_TARGETS}"
                     export NDK="${CURDIR}/base/toolchain/android-ndk-r15c"
                 fi
             fi
-            [ -e "${CURDIR}/base/toolchain/android-toolchain/bin/arm-linux-androideabi-gcc" ] || {
+            [ -e "${CURDIR}/base/toolchain/android-toolchain-${ANDROID_ARCH}/bin/" ] || {
                 { [ -e "${NDK}" ] || make -C "${CURDIR}/base/toolchain" android-ndk; }
                 make android-toolchain
                 assert_ret_zero $?
@@ -449,7 +460,7 @@ TARGET:
                 adb logcat -c
                 # uninstall existing package to make sure *everything* is gone from memory
                 adb uninstall "org.koreader.launcher"
-                adb install "koreader-android-arm-linux-androideabi-${VERSION}.apk"
+                adb install "koreader-android-${ANDROID_FULL_ARCH_APK}-${VERSION}.apk"
                 # there's no adb run so we do this…
                 adb shell monkey -p org.koreader.launcher -c android.intent.category.LAUNCHER 1
                 adb logcat