Update HidlInstrumentor.

* Instead of dlsym method HIDL_INSTRUMENTATION_FUNCTION, dlsym
  HIDL_INSTRUMENTATION_FUNCTION + insterface_name.
* This enables a single profiler library that contains the profiling
  method for all the interfaces defined within the same hidl package.

Test: mma for hardware/interface.
      local test with vts.
Change-Id: I076841ea8a565c489b45303e5ca496806d5d10be
diff --git a/base/include/hidl/HidlSupport.h b/base/include/hidl/HidlSupport.h
index 3f7248c..7fb052b 100644
--- a/base/include/hidl/HidlSupport.h
+++ b/base/include/hidl/HidlSupport.h
@@ -838,7 +838,9 @@
             const char *method,
             std::vector<void *> *args)>;
 
-    explicit HidlInstrumentor(const std::string &prefix);
+    explicit HidlInstrumentor(
+            const std::string &package,
+            const std::string &insterface);
     virtual ~HidlInstrumentor();
 
  protected:
@@ -870,7 +872,10 @@
     // Flag whether to enable instrumentation.
     bool mEnableInstrumentation;
     // Prefix to lookup the instrumentation libraries.
-    std::string mInstrumentationLibPrefix;
+    std::string mInstrumentationLibPackage;
+    // Used for dlsym to load the profiling method for given interface.
+    std::string mInterfaceName;
+
 };
 
 ///////////////////// toString functions