create gBsConstructorMap; add wrapPassthrough

Similar to gBnConstructorMap, this map helps wrapping a local
interface with the smallest BsFoo possible. They are added
in Static.h/cpp.

Added HidlPassthroughSupport.h/cpp to hold wrapPassthrough.

Also fixes a few Return object isOk() checks.

Fix: 33307350

Test: hidl_test

Change-Id: I92a7283699bfe5b022df5ab5a9ead5690477ea97
diff --git a/transport/Android.bp b/transport/Android.bp
index 4f97ff6..5614ffb 100644
--- a/transport/Android.bp
+++ b/transport/Android.bp
@@ -52,6 +52,7 @@
 
     srcs: [
         "HidlBinderSupport.cpp",
+        "HidlPassthroughSupport.cpp",
         "ServiceManagement.cpp",
         "Static.cpp"
     ],