libgui/SurfaceFlinger: Add getConsumerName

Adds a getConsumerName method to IGraphicBufferProducer and Surface.
Currently, the name is cached inside of IGBP and is update on connect
and dequeueBuffer, which should be good enough for most uses.

Bug: 6667401
Change-Id: I22c7881d778e495cf8276de7bbcd769e52429915
diff --git a/libs/gui/IGraphicBufferProducer.cpp b/libs/gui/IGraphicBufferProducer.cpp
index cfe726b..d7a7885 100644
--- a/libs/gui/IGraphicBufferProducer.cpp
+++ b/libs/gui/IGraphicBufferProducer.cpp
@@ -48,6 +48,7 @@
     ALLOCATE_BUFFERS,
     ALLOW_ALLOCATION,
     SET_GENERATION_NUMBER,
+    GET_CONSUMER_NAME,
 };
 
 class BpGraphicBufferProducer : public BpInterface<IGraphicBufferProducer>
@@ -296,6 +297,17 @@
         }
         return result;
     }
+
+    virtual String8 getConsumerName() const {
+        Parcel data, reply;
+        data.writeInterfaceToken(IGraphicBufferProducer::getInterfaceDescriptor());
+        status_t result = remote()->transact(GET_CONSUMER_NAME, data, &reply);
+        if (result != NO_ERROR) {
+            ALOGE("getConsumerName failed to transact: %d", result);
+            return String8("TransactFailed");
+        }
+        return reply.readString8();
+    }
 };
 
 // Out-of-line virtual method definition to trigger vtable emission in this
@@ -467,6 +479,11 @@
             reply->writeInt32(result);
             return NO_ERROR;
         }
+        case GET_CONSUMER_NAME: {
+            CHECK_INTERFACE(IGraphicBufferProducer, data, reply);
+            reply->writeString8(getConsumerName());
+            return NO_ERROR;
+        }
     }
     return BBinder::onTransact(code, data, reply, flags);
 }