pt 1 in reviving the android build (copied from pm 28a1, wish me luck)

mobile/android/thirdparty/com/adjust/sdk/ActivityKind.java

@@ -0,0 +1,35 @@
+package com.adjust.sdk;
+
+public enum ActivityKind {
+    UNKNOWN, SESSION, EVENT, CLICK, ATTRIBUTION;
+
+    public static ActivityKind fromString(String string) {
+        if ("session".equals(string)) {
+            return SESSION;
+        } else if ("event".equals(string)) {
+            return EVENT;
+        } else if ("click".equals(string)) {
+            return CLICK;
+        } else if ("attribution".equals(string)) {
+            return ATTRIBUTION;
+        } else {
+            return UNKNOWN;
+        }
+    }
+
+    @Override
+    public String toString() {
+        switch (this) {
+            case SESSION:
+                return "session";
+            case EVENT:
+                return "event";
+            case CLICK:
+                return "click";
+            case ATTRIBUTION:
+                return "attribution";
+            default:
+                return "unknown";
+        }
+    }
+}