Apply revised TrustAgent API

Bug: 14997466
Change-Id: I81042e058a20f28603a11471882f3dcfc4f8b13c
diff --git a/services/core/java/com/android/server/trust/TrustManagerService.java b/services/core/java/com/android/server/trust/TrustManagerService.java
index 9061f96..a39c116 100644
--- a/services/core/java/com/android/server/trust/TrustManagerService.java
+++ b/services/core/java/com/android/server/trust/TrustManagerService.java
@@ -221,8 +221,8 @@
                 // Drain preamble.
             }
             String nodeName = parser.getName();
-            if (!"trust_agent".equals(nodeName)) {
-                Slog.w(TAG, "Meta-data does not start with trust_agent tag");
+            if (!"trust-agent".equals(nodeName)) {
+                Slog.w(TAG, "Meta-data does not start with trust-agent tag");
                 return null;
             }
             TypedArray sa = res