Coalesce CameraThreadState and AttributionAndPermissionUtils

The calling UID / PID are ways of attributing the camera client to
the caller, and so fall under the scope of this utility class.

Change-Id: I06af9264d1ca68eaccc4c6e4c01b9d09dd20e5ad
Bug: 190657833
Test: CtsCameraTestCases
diff --git a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
index 830a8e8..db6457f 100644
--- a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
+++ b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
@@ -19,6 +19,7 @@
 #include <android/content/AttributionSourceState.h>
 #include <android/permission/PermissionChecker.h>
 #include <binder/BinderService.h>
+#include <private/android_filesystem_config.h>
 
 namespace android {
 
@@ -40,6 +41,12 @@
         mCameraService = cameraService;
     }
 
+    // Utilities handling Binder calling identities (previously in CameraThreadState)
+    virtual int getCallingUid();
+    virtual int getCallingPid();
+    virtual int64_t clearCallingIdentity();
+    virtual void restoreCallingIdentity(int64_t token);
+
     /**
      * Pre-grants the permission if the attribution source uid is for an automotive
      * privileged client. Otherwise uses system service permission checker to check
@@ -129,6 +136,28 @@
         return attributionSource;
     }
 
+    int getCallingUid() const {
+        return mAttributionAndPermissionUtils->getCallingUid();
+    }
+
+    int getCallingPid() const {
+        return mAttributionAndPermissionUtils->getCallingPid();
+    }
+
+    int64_t clearCallingIdentity() const {
+        return mAttributionAndPermissionUtils->clearCallingIdentity();
+    }
+
+    void restoreCallingIdentity(int64_t token) const {
+        mAttributionAndPermissionUtils->restoreCallingIdentity(token);
+    }
+
+    // The word 'System' here does not refer to callers only on the system
+    // partition. They just need to have an android system uid.
+    bool callerHasSystemUid() const {
+        return (getCallingUid() < AID_APP_START);
+    }
+
     bool hasPermissionsForCamera(int callingPid, int callingUid) const {
         return hasPermissionsForCamera(std::string(), callingPid, callingUid);
     }