Move TaskRunner and SynchronizedQueue to details

Bug: 36433220
Test: compiles
Test: hidl_test
Test: libhidl_test
Change-Id: Ia48bf9abba293f177ec2f6cfab49da5422a59b82
diff --git a/base/TaskRunner.cpp b/base/TaskRunner.cpp
index 2f7d89c..78add4c 100644
--- a/base/TaskRunner.cpp
+++ b/base/TaskRunner.cpp
@@ -19,6 +19,7 @@
 
 namespace android {
 namespace hardware {
+namespace details {
 
 TaskRunner::TaskRunner() {
     bool *running = mRunning = new bool();
@@ -43,6 +44,7 @@
     });
 }
 
+} // namespace details
 } // namespace hardware
 } // namespace android