power: Add property check for EXPENSIVE_RENDERING

Detect the support status of EXPENSIVE_RENDERING mode based on the
vendor property, which can be configured per target.

Change-Id: I39ed53f5df506bb8b7a714138d35e5b29bcfa4a5
CRs-Fixed: 3364809

Power.cpp

@@ -96,6 +96,12 @@ ndk::ScopedAStatus Power::isModeSupported(Mode type, bool* _aidl_return) {
 
     switch(type){
         case Mode::EXPENSIVE_RENDERING:
+            if (is_expensive_rendering_supported()) {
+                *_aidl_return = true;
+            } else {
+                *_aidl_return = false;
+            }
+            break;
         case Mode::INTERACTIVE:
         case Mode::SUSTAINED_PERFORMANCE:
         case Mode::FIXED_PERFORMANCE: