Merge MemoryCoordinator and MemoryCoordinatorImpl into one class

content/browser/memory/memory_monitor_android.cc

Index: content/browser/memory/memory_monitor_android.cc
diff --git a/content/browser/memory/memory_monitor_android.cc b/content/browser/memory/memory_monitor_android.cc
index ef6afa2d06ae6dd330d2f621ea16f8bab48e3e04..08fbd0ebcf379d03c57dfc61f8a2168750c6980e 100644
--- a/content/browser/memory/memory_monitor_android.cc
+++ b/content/browser/memory/memory_monitor_android.cc
@@ -74,8 +74,7 @@ static void OnTrimMemory(JNIEnv* env,
                          const base::android::JavaParamRef<jclass>& jcaller,
                          jint level) {
   DCHECK(level >= 0 && level <= kTrimMemoryLevelMax);
-  auto* coordinator =
-      static_cast<MemoryCoordinatorImpl*>(MemoryCoordinator::GetInstance());
+  auto* coordinator = MemoryCoordinatorImpl::GetInstance();
 
   auto state = coordinator->GetGlobalMemoryState();
   switch (state) {