Remove no-longer-needed IsBusy...() stuff.

mojo/edk/system/data_pipe.cc

Index: mojo/edk/system/data_pipe.cc
diff --git a/mojo/edk/system/data_pipe.cc b/mojo/edk/system/data_pipe.cc
index d671a7625e93043f18e3a09f7aea4e76aeaf5b1d..4a6d5ae0ba3956d6df54fc40700916ef17c5c5a4 100644
--- a/mojo/edk/system/data_pipe.cc
+++ b/mojo/edk/system/data_pipe.cc
@@ -457,11 +457,6 @@ bool DataPipe::ProducerEndSerialize(
   return rv;
 }
 
-bool DataPipe::ProducerIsBusy() const {
-  MutexLocker locker(&mutex_);
-  return producer_in_two_phase_write_no_lock();
-}
-
 void DataPipe::ConsumerCancelAllState() {
   MutexLocker locker(&mutex_);
   ConsumerCancelAllStateNoLock();
@@ -681,11 +676,6 @@ bool DataPipe::ConsumerEndSerialize(
   return rv;
 }
 
-bool DataPipe::ConsumerIsBusy() const {
-  MutexLocker locker(&mutex_);
-  return consumer_in_two_phase_read_no_lock();
-}
-
 DataPipe::DataPipe(bool has_local_producer,
                    bool has_local_consumer,
                    const MojoCreateDataPipeOptions& validated_options,