Add IBinder::setRpcClient

This function allows a certain service to handle RPC
calls from a given socket fd, with a given thread pool
size.

Test: binderRpcTest
Test: binderLibTest
Bug: 182914638
Change-Id: Idee3eb004af15d57a701800a103f6f0c337e49f5
diff --git a/libs/binder/ProcessState.cpp b/libs/binder/ProcessState.cpp
index f7ca1e6..3095607 100644
--- a/libs/binder/ProcessState.cpp
+++ b/libs/binder/ProcessState.cpp
@@ -359,6 +359,14 @@
     return result;
 }
 
+size_t ProcessState::getThreadPoolMaxThreadCount() const {
+    // may actually be one more than this, if join is called
+    if (mThreadPoolStarted) return mMaxThreads;
+    // must not be initialized or maybe has poll thread setup, we
+    // currently don't track this in libbinder
+    return 0;
+}
+
 status_t ProcessState::enableOnewaySpamDetection(bool enable) {
     uint32_t enableDetection = enable ? 1 : 0;
     if (ioctl(mDriverFD, BINDER_ENABLE_ONEWAY_SPAM_DETECTION, &enableDetection) == -1) {