workaround for coverage bug (for now!)

see android bug report https://code.google.com/p/android/issues/detail?id=170607

OpenKeychain/build.gradle

@@ -114,7 +114,7 @@ android {
         versionCode 32300
         versionName "3.2.3"
         applicationId "org.sufficientlysecure.keychain"
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        testInstrumentationRunner "org.sufficientlysecure.keychain.JacocoWorkaroundJUnitRunner"
     }
 
     compileOptions {
@@ -217,7 +217,10 @@ task jacocoTestReport(type:JacocoReport) {
             "${buildDir}/generated/source/buildConfig/debug",
             "${buildDir}/generated/source/r/debug"
     ])
-    executionData = files("${buildDir}/jacoco/testDebug.exec")
+    executionData = files([
+        "${buildDir}/jacoco/testDebug.exec",
+        "${buildDir}/outputs/code-coverage/connected/coverage.ec"
+    ])
 
     reports {
         xml.enabled = true

OpenKeychain/src/androidTest/java/org/sufficientlysecure/keychain/JacocoWorkaroundJUnitRunner.java

@@ -0,0 +1,29 @@
+package org.sufficientlysecure.keychain;
+
+
+import java.lang.reflect.Method;
+
+import android.os.Bundle;
+import android.support.test.runner.AndroidJUnitRunner;
+
+
+public class JacocoWorkaroundJUnitRunner extends AndroidJUnitRunner {
+    static {
+            System.setProperty("jacoco-agent.destfile", "/data/data/"
+                    + BuildConfig.APPLICATION_ID + "/coverage.ec");
+    }
+
+    @Override
+    public void finish(int resultCode, Bundle results) {
+        try {
+            Class rt = Class.forName("org.jacoco.agent.rt.RT");
+            Method getAgent = rt.getMethod("getAgent");
+            Method dump = getAgent.getReturnType().getMethod("dump", boolean.class);
+            Object agent = getAgent.invoke(null);
+            dump.invoke(agent, false);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        super.finish(resultCode, results);
+    }
+}