cmsdk: Ensure CMHW feature constants aren't optimized out

 * The preferences constraints system uses reflection to look up
   fields via strings, we need to ensure they are not optimized
   out by Proguard. Alternatively we can manually enumerate them,
   but it's yet another list of constants to maintain. We should
   have used a proper enumeration to begin with, but so it goes.
 * The @VisibleForTesting annotation is honored by the platform for
   ensuring that Proguard doesn't stomp fields. The support library
   has an @Keep annotation, but it's only supported by Gradle. If
   it becomes supported by the platform in the future, switch to
   it instead.
 * Also add tests for all of this.

Change-Id: I9f324e003e2a9de5604085b978d5f95bdd098d32

1 files changed, 24 insertions, 2 deletions

diff --git a/tests/src/org/cyanogenmod/tests/hardware/CMHardwareTest.java b/tests/src/org/cyanogenmod/tests/hardware/CMHardwareTest.java
index a65f632c..556246e3 100644
--- a/tests/src/org/cyanogenmod/tests/hardware/CMHardwareTest.java
+++ b/tests/src/org/cyanogenmod/tests/hardware/CMHardwareTest.java
@@ -51,6 +51,23 @@ public class CMHardwareTest extends TestActivity {
             CMHardwareManager.FEATURE_PERSISTENT_STORAGE
     );
 
+    private static final List<String> FEATURE_STRINGS = Arrays.asList(
+            "FEATURE_ADAPTIVE_BACKLIGHT",
+            "FEATURE_COLOR_ENHANCEMENT",
+            "FEATURE_DISPLAY_COLOR_CALIBRATION",
+            "FEATURE_DISPLAY_GAMMA_CALIBRATION",
+            "FEATURE_HIGH_TOUCH_SENSITIVITY",
+            "FEATURE_KEY_DISABLE",
+            "FEATURE_LONG_TERM_ORBITS",
+            "FEATURE_SERIAL_NUMBER",
+            "FEATURE_SUNLIGHT_ENHANCEMENT",
+            "FEATURE_TAP_TO_WAKE",
+            "FEATURE_TOUCH_HOVERING",
+            "FEATURE_AUTO_CONTRAST",
+            "FEATURE_DISPLAY_MODES",
+            "FEATURE_PERSISTENT_STORAGE"
+    );
+
     private static final List<Integer> BOOLEAN_FEATURES = Arrays.asList(
             CMHardwareManager.FEATURE_ADAPTIVE_BACKLIGHT,
             CMHardwareManager.FEATURE_COLOR_ENHANCEMENT,
@@ -160,10 +177,15 @@ public class CMHardwareTest extends TestActivity {
                 @Override
                 protected void run() {
                     StringBuilder builder = new StringBuilder();
+                    int i = 0;
                     for (int feature : FEATURES) {
+                        boolean supported = mHardwareManager.isSupported(feature);
+                        if (mHardwareManager.isSupported(FEATURE_STRINGS.get(i)) != supported) {
+                            throw new RuntimeException("Internal error, feature string lookup failed");
+                        }
+                        i++;
                         builder.append("Feature " + feature + "\n")
-                                .append("is supported " + mHardwareManager.isSupported(feature)
-                                        + "\n");
+                                .append("is supported " + supported + "\n");
                     }
                     Toast.makeText(CMHardwareTest.this, "Supported features " +
                                     builder.toString(),