ueventd: require opt-in for modalias handling

Some devices have modules.alias and modules.dep for modprobe and other
purposes but do not want to opt into ueventd auto loading their
modules.  Therefore we add a flag that can be added to ueventd
configuration files to opt into this behavior.

Bug: 111916071
Bug: 112048758
Test: check that modules are loaded with this opt-in
Test: check that modules are not loaded without this opt-in
Change-Id: Ifb281b273059b4671eea1ca5bc726c9e79f3adfb
diff --git a/init/modalias_handler.h b/init/modalias_handler.h
index e79da32..3247c86 100644
--- a/init/modalias_handler.h
+++ b/init/modalias_handler.h
@@ -16,22 +16,23 @@
 
 #pragma once
 
-#include "result.h"
-#include "uevent.h"
-
 #include <string>
 #include <unordered_map>
 #include <vector>
 
+#include "result.h"
+#include "uevent.h"
+#include "uevent_handler.h"
+
 namespace android {
 namespace init {
 
-class ModaliasHandler {
+class ModaliasHandler : public UeventHandler {
   public:
     ModaliasHandler();
-    ~ModaliasHandler(){};
+    virtual ~ModaliasHandler() = default;
 
-    void HandleModaliasEvent(const Uevent& uevent);
+    void HandleUevent(const Uevent& uevent) override;
 
   private:
     Result<Success> InsmodWithDeps(const std::string& module_name, const std::string& args);