fw/ApkWorkload: Allow workloads to provide apk arguments

In some workloads it is beneficial to be able to provide arguments
when launching the required APK. Add a new `arpk_arguments` property
to allow a workload to provide a dict of parameter names and values
that should be used when launching the APK.

The python types of the parameters are used to determine the data
type provided to the APK. Currently supported types are string, bool,
int and float.

wa/utils/android.py

@@ -16,6 +16,7 @@
 import logging
 import os
 from datetime import datetime
+from shlex import quote
 
 from devlib.utils.android import ApkInfo as _ApkInfo
 
@@ -196,3 +197,29 @@ def get_cacheable_apk_info(path):
 
 
 apk_info_cache = ApkInfoCache()
+
+
+def build_apk_launch_command(package, activity=None, apk_args=None):
+    args_string = ''
+    if apk_args:
+        for k, v in apk_args.items():
+            if isinstance(v, str):
+                arg = '--es'
+                v = quote(v)
+            elif isinstance(v, float):
+                arg = '--ef'
+            elif isinstance(v, bool):
+                arg = '--ez'
+            elif isinstance(v, int):
+                arg = '--ei'
+            else:
+                raise ValueError('Unable to encode {} {}'.format(v, type(v)))
+
+            args_string = '{} {} {} {}'.format(args_string, arg, k, v)
+
+    if not activity:
+        cmd = 'am start -W {} {}'.format(package, args_string)
+    else:
+        cmd = 'am start -W -n {}/{} {}'.format(package, activity, args_string)
+
+    return cmd