bufferpool2: handle transfer to closed connection

Handle transfer to closed connection properly. Also avoid spinlocking
during invalidation.

Bug: 139506073
Test: atest CtsMediaTestCases -- --module-arg CtsMediaTestCases:size:small
Merged-In: I9037ab0bde48a51b2b97158ecd0086dac84f8b26
Change-Id: I9037ab0bde48a51b2b97158ecd0086dac84f8b26
diff --git a/media/bufferpool/1.0/AccessorImpl.cpp b/media/bufferpool/1.0/AccessorImpl.cpp
index fa17f15..a5366f6 100644
--- a/media/bufferpool/1.0/AccessorImpl.cpp
+++ b/media/bufferpool/1.0/AccessorImpl.cpp
@@ -151,6 +151,7 @@
                 newConnection->initialize(accessor, id);
                 *connection = newConnection;
                 *pConnectionId = id;
+                mBufferPool.mConnectionIds.insert(id);
                 ++sSeqId;
             }
         }
@@ -305,7 +306,12 @@
         found->second->mSenderValidated = true;
         return true;
     }
-    // TODO: verify there is target connection Id
+    if (mConnectionIds.find(message.targetConnectionId) == mConnectionIds.end()) {
+        // N.B: it could be fake or receive connection already closed.
+        ALOGD("bufferpool %p receiver connection %lld is no longer valid",
+              this, (long long)message.targetConnectionId);
+        return false;
+    }
     mStats.onBufferSent();
     mTransactions.insert(std::make_pair(
             message.transactionId,
@@ -450,6 +456,7 @@
             }
         }
     }
+    mConnectionIds.erase(connectionId);
     return true;
 }