power: Add support for EXPENSIVE_RENDERING

When background_blur is enabled, the rendering can be expensive
and many janks will occur. So, need to support the mode in power
module and pass it to perf-hal to handle.

Change-Id: I5bab53e72134d76201d9fc28b9bdae4185790deb
CRs-Fixed: 3278491

power-common.c

@@ -49,6 +49,7 @@
 #include "power-common.h"
 
 static struct hint_handles handles[NUM_HINTS];
+static int handleER = 0;
 
 void power_init()
 {
@@ -115,6 +116,15 @@ void power_hint(power_hint_t hint, void *data)
     }
 }
 
+void set_expensive_rendering(bool enabled)
+{
+    if (enabled) {
+        handleER = perf_hint_enable(PERF_HINT_EXPENSIVE_RENDERING, 0);
+    } else if (handleER > 0) {
+        release_request(handleER);
+    }
+}
+
 int __attribute__ ((weak)) set_interactive_override(int on)
 {
     return HINT_NONE;