health: use recursive_mutex.

Need to use an reentrant lock.

Bug: 117167903
Test: vts
Change-Id: I25a366e06ed9d983823f7276668b7f45ddcf1c2b
diff --git a/health/2.0/default/Health.cpp b/health/2.0/default/Health.cpp
index e02bfa9..4a4bee0 100644
--- a/health/2.0/default/Health.cpp
+++ b/health/2.0/default/Health.cpp
@@ -46,7 +46,7 @@
     }
 
     {
-        std::lock_guard<std::mutex> _lock(callbacks_lock_);
+        std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
         callbacks_.push_back(callback);
         // unlock
     }
@@ -65,7 +65,7 @@
     if (callback == nullptr) return false;
 
     bool removed = false;
-    std::lock_guard<std::mutex> _lock(callbacks_lock_);
+    std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
     for (auto it = callbacks_.begin(); it != callbacks_.end();) {
         if (interfacesEqual(*it, callback)) {
             it = callbacks_.erase(it);
@@ -175,7 +175,7 @@
     healthInfo->diskStats = stats;
     healthInfo->storageInfos = info;
 
-    std::lock_guard<std::mutex> _lock(callbacks_lock_);
+    std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
     for (auto it = callbacks_.begin(); it != callbacks_.end();) {
         auto ret = (*it)->healthInfoChanged(*healthInfo);
         if (!ret.isOk() && ret.isDeadObject()) {
diff --git a/health/2.0/default/include/health2/Health.h b/health/2.0/default/include/health2/Health.h
index 134cdc6..b960358 100644
--- a/health/2.0/default/include/health2/Health.h
+++ b/health/2.0/default/include/health2/Health.h
@@ -31,12 +31,10 @@
     // Should only be called by implementation itself (-impl, -service).
     // Clients should not call this function. Instead, initInstance() initializes and returns the
     // global instance that has fewer functions.
-    // TODO(b/62229583): clean up and hide these functions after update() logic is simplified.
     static sp<Health> getImplementation();
 
     Health(struct healthd_config* c);
 
-    // TODO(b/62229583): clean up and hide these functions after update() logic is simplified.
     void notifyListeners(HealthInfo* info);
 
     // Methods from IHealth follow.
@@ -61,7 +59,7 @@
    private:
     static sp<Health> instance_;
 
-    std::mutex callbacks_lock_;
+    std::recursive_mutex callbacks_lock_;
     std::vector<sp<IHealthInfoCallback>> callbacks_;
     std::unique_ptr<BatteryMonitor> battery_monitor_;