Don't use shader disk cache on emulator

bug: 71900691

Emulator user might switch renderers, migrate a snapshot to a different
machine with a different shader binary format, etc.

Plus, program binaries don't seem to work so well on some desktop GPUs.

Change-Id: I0c6239acbd556097494aa903d6603c963d3141cb
diff --git a/libs/hwui/Properties.cpp b/libs/hwui/Properties.cpp
index 4243e7e..6cd283a 100644
--- a/libs/hwui/Properties.cpp
+++ b/libs/hwui/Properties.cpp
@@ -61,6 +61,8 @@
 bool Properties::skpCaptureEnabled = false;
 bool Properties::enableRTAnimations = true;
 
+bool Properties::runningInEmulator = false;
+
 static int property_get_int(const char* key, int defaultValue) {
     char buf[PROPERTY_VALUE_MAX] = {
             '\0',
@@ -135,6 +137,8 @@
     skpCaptureEnabled = property_get_bool("ro.debuggable", false) &&
                         property_get_bool(PROPERTY_CAPTURE_SKP_ENABLED, false);
 
+    runningInEmulator = property_get_bool(PROPERTY_QEMU_KERNEL, false);
+
     return (prevDebugLayersUpdates != debugLayersUpdates) || (prevDebugOverdraw != debugOverdraw) ||
            (prevDebugStencilClip != debugStencilClip);
 }