Add util function to get the APK path

Use "pm list package -f" to find where the APK is actually installed on
the device.

app/src/adb/adb.h

@@ -15,6 +15,8 @@
 
 #define SC_ADB_SILENT (SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR)
 
+#define SC_ANDROID_PACKAGE "com.genymobile.scrcpy"
+
 const char *
 sc_adb_get_executable(void);
 
@@ -114,4 +116,11 @@ sc_adb_getprop(struct sc_intr *intr, const char *serial, const char *prop,
 char *
 sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags);
 
+/**
+ * Return the path of the installed APK for com.genymobile.scrcpy (if any)
+ */
+char *
+sc_adb_get_installed_apk_path(struct sc_intr *intr, const char *serial,
+                              unsigned flags);
+
 #endif