DO NOT MERGE: camera2: Performance potpourri.

Bug: 16208403
Bug: 15116722

Fixes many of the performance issues in the Camera2 API and
LEGACY mode CPU path, including:
- Only call getParameters/setParameters when the request has changed.
- Cache Request/Result objects.
- Cache object hashes for long-lived CameraMetadata, TypeReference,
  and Key objects with frequently used hash methods.
- Switch to Command pattern instead of repeated if/equals calls.
  in frequently hit CameraMetadata get/set methods.
- Move string construction for logging behind flags to avoid extra
  StringBuilder calls in frequently acquired lock methods.
- Cache results from frequently used JNI calls in object Builders.

Change-Id: I77bc4a023d4fe8bc46efcf771ff18ee268dcb9a9

1 files changed, 13 insertions, 0 deletions

diff --git a/core/java/android/hardware/Camera.java b/core/java/android/hardware/Camera.java
index 4c73e6a..eadfa73 100644
--- a/core/java/android/hardware/Camera.java
+++ b/core/java/android/hardware/Camera.java
@@ -2423,6 +2423,19 @@ public class Camera {
             return Camera.this;
         }
 
+
+        /**
+         * Value equality check.
+         *
+         * @hide
+         */
+        public boolean same(Parameters other) {
+            if (this == other) {
+                return true;
+            }
+            return other != null && Parameters.this.mMap.equals(other.mMap);
+        }
+
         /**
          * Writes the current Parameters to the log.
          * @hide