Fix flaky TestWakeupClientServiceImplUnitTest.

This CL fixed two possible issues: 1. mServerStarted is not reset
to false for each test case. 2. pollOnce should be used instead of
pollAll since pollAll might swallow wake.

Test: atest --host TestWakeupClientServerHostUnitTest
Bug: 333673876
Change-Id: Id705d6257c54a2e2711aff6018abf2ea65b0f691
diff --git a/automotive/remoteaccess/test_grpc_server/impl/src/TestWakeupClientServiceImpl.cpp b/automotive/remoteaccess/test_grpc_server/impl/src/TestWakeupClientServiceImpl.cpp
index 5d33fcb..515dc98 100644
--- a/automotive/remoteaccess/test_grpc_server/impl/src/TestWakeupClientServiceImpl.cpp
+++ b/automotive/remoteaccess/test_grpc_server/impl/src/TestWakeupClientServiceImpl.cpp
@@ -169,7 +169,8 @@
     Looper::setForThread(mLooper);
 
     while (true) {
-        mLooper->pollAll(/*timeoutMillis=*/-1);
+        // Don't use pollAll since it might swallow wake.
+        mLooper->pollOnce(/*timeoutMillis=*/-1);
         if (mServerStopped) {
             return;
         }
diff --git a/automotive/remoteaccess/test_grpc_server/impl/test/TestWakeupClientServiceImplUnitTest.cpp b/automotive/remoteaccess/test_grpc_server/impl/test/TestWakeupClientServiceImplUnitTest.cpp
index dd08e32..a7927f5 100644
--- a/automotive/remoteaccess/test_grpc_server/impl/test/TestWakeupClientServiceImplUnitTest.cpp
+++ b/automotive/remoteaccess/test_grpc_server/impl/test/TestWakeupClientServiceImplUnitTest.cpp
@@ -53,6 +53,9 @@
   public:
     virtual void SetUp() override {
         int selectedPort = 0;
+        mServerStarted = false;
+        mService.reset();
+        mServer.reset();
         mServerThread = std::thread([this, &selectedPort] {
             mService = std::make_unique<MyTestWakeupClientServiceImpl>();
             ServerBuilder builder;