Revert "Let InputFlinger create the server InputChannel"

Revert submission 12594832-hide_server_input_channel

Reason for revert: <INSERT REASONING HERE>
Reverted Changes:
I7033caf10:Use new create/removeInputChannel().
I35f768c8a:Let InputFlinger create the server InputChannel

Bug: 169083114
Bug: 169088136
Change-Id: Ib6945129936006682cd03cea614fbdfd4f5fa008
diff --git a/services/inputflinger/benchmarks/InputDispatcher_benchmarks.cpp b/services/inputflinger/benchmarks/InputDispatcher_benchmarks.cpp
index 46bc055..b645d69 100644
--- a/services/inputflinger/benchmarks/InputDispatcher_benchmarks.cpp
+++ b/services/inputflinger/benchmarks/InputDispatcher_benchmarks.cpp
@@ -129,14 +129,17 @@
 protected:
     explicit FakeInputReceiver(const sp<InputDispatcher>& dispatcher, const std::string name)
           : mDispatcher(dispatcher) {
-        mClientChannel = *mDispatcher->createInputChannel(name);
+        std::unique_ptr<InputChannel> serverChannel, clientChannel;
+        InputChannel::openInputChannelPair(name, serverChannel, clientChannel);
+        mServerChannel = std::move(serverChannel);
+        mClientChannel = std::move(clientChannel);
         mConsumer = std::make_unique<InputConsumer>(mClientChannel);
     }
 
     virtual ~FakeInputReceiver() {}
 
     sp<InputDispatcher> mDispatcher;
-    std::shared_ptr<InputChannel> mClientChannel;
+    std::shared_ptr<InputChannel> mServerChannel, mClientChannel;
     std::unique_ptr<InputConsumer> mConsumer;
     PreallocatedInputEventFactory mEventFactory;
 };
@@ -149,12 +152,14 @@
     FakeWindowHandle(const std::shared_ptr<InputApplicationHandle>& inputApplicationHandle,
                      const sp<InputDispatcher>& dispatcher, const std::string name)
           : FakeInputReceiver(dispatcher, name), mFrame(Rect(0, 0, WIDTH, HEIGHT)) {
+        mDispatcher->registerInputChannel(mServerChannel);
+
         inputApplicationHandle->updateInfo();
         mInfo.applicationInfo = *inputApplicationHandle->getInfo();
     }
 
     virtual bool updateInfo() override {
-        mInfo.token = mClientChannel->getConnectionToken();
+        mInfo.token = mServerChannel->getConnectionToken();
         mInfo.name = "FakeWindowHandle";
         mInfo.type = InputWindowInfo::Type::APPLICATION;
         mInfo.dispatchingTimeout = DISPATCHING_TIMEOUT;