Reduce 'android-18' duplication, as originally done by wenderen

Use android.platform (and $ANDROID_PLATFORM) for configuration, apply 'android-18' default

python/servo/command_base.py

@@ -178,6 +178,7 @@ def resolverelative(category, key):
         self.config["android"].setdefault("sdk", "")
         self.config["android"].setdefault("ndk", "")
         self.config["android"].setdefault("toolchain", "")
+        self.config["android"].setdefault("platform", "android-18")
         self.config["android"].setdefault("target", "arm-linux-androideabi")
 
         self.config.setdefault("gonk", {})
@@ -318,6 +319,8 @@ def build_env(self, gonk=False, hosts_file_path=None, target=None):
             env["ANDROID_NDK"] = self.config["android"]["ndk"]
         if self.config["android"]["toolchain"]:
             env["ANDROID_TOOLCHAIN"] = self.config["android"]["toolchain"]
+        if self.config["android"]["platform"]:
+            env["ANDROID_PLATFORM"] = self.config["android"]["platform"]
 
         if gonk:
             if self.config["gonk"]["b2g"]:

servobuild.example

@@ -41,10 +41,11 @@ debug-mozjs = false
 
 # Android information
 [android]
-# Defaults to the value of $ANDROID_SDK, $ANDROID_NDK, $ANDROID_TOOLCHAIN respectively
+# Defaults to the value of $ANDROID_SDK, $ANDROID_NDK, $ANDROID_TOOLCHAIN, $ANDROID_PLATFORM respectively
 #sdk = "/opt/android-sdk"
 #ndk = "/opt/android-ndk"
 #toolchain = "/opt/android-toolchain"
+#platform = "android-18"
 
 # Gonk information
 # Please fill the ndk/toolchain for Android too

support/android/apk/build.xml

@@ -36,17 +36,9 @@
     <condition property="sdk.dir" value="${env.ANDROID_HOME}">
         <isset property="env.ANDROID_HOME" />
     </condition>
-
-    <!-- The project.properties file is created and updated by the 'android'
-         tool, as well as ADT.
-
-         This contains project specific properties such as project target, and library
-         dependencies. Lower level build properties are stored in ant.properties
-         (or in .classpath for Eclipse projects).
-
-         This file is an integral part of the build system for your
-         application and should be checked into Version Control Systems. -->
-    <loadproperties srcFile="project.properties" />
+    <condition property="target" value="${env.ANDROID_PLATFORM}">
+        <isset property="env.ANDROID_PLATFORM" />
+    </condition>
 
     <!-- quick check on sdk.dir -->
     <fail

support/android/apk/jni/Application.mk

@@ -1,2 +1,2 @@
 APP_ABI := armeabi
-APP_PLATFORM := android-18
+APP_PLATFORM := $(ANDROID_PLATFORM)

support/android/build-apk/src/main.rs

@@ -27,6 +27,11 @@ fn main() {
     let ndk_path = env::var("NDK_HOME").ok().expect("Please set the NDK_HOME environment variable");
     let ndk_path = Path::new(&ndk_path);
 
+    // Get the target android platform from ANDROID_PLATFORM env. Expecting "android-{version}"
+    let android_platform = env::var("ANDROID_PLATFORM")
+        .ok()
+        .expect("Please set the ANDROID_PLATFORM environment variable")
+
     // Get the standalone NDK path from NDK_STANDALONE env.
     //  let standalone_path = env::var("NDK_STANDALONE").ok().unwrap_or("/opt/ndk_standalone".to_string());
     //  let standalone_path = Path::new(&standalone_path);
@@ -97,7 +102,7 @@ fn main() {
                                   .arg("--name")
                                   .arg("Servo")
                                   .arg("--target")
-                                  .arg("android-18")
+                                  .arg(&android_platform)
                                   .arg("--path")
                                   .arg(".")
                                   .stdout(Stdio::inherit())

support/android/openssl.sh

@@ -36,7 +36,7 @@ _ANDROID_ARCH=arch-arm
 # Android 5.0, there will likely be another platform added (android-22?).
 # This value is always used.
 # _ANDROID_API="android-14"
-_ANDROID_API="android-18"
+_ANDROID_API="$ANDROID_PLATFORM"
 # _ANDROID_API="android-19"
 
 #####################################################################