Add myself to OWNERS

R=lalitm@google.com,hjd@google.com,primiano@google.com

Change-Id: I5b5add35874f1e3127a1454df9adc71f5c758364
diff --git a/OWNERS b/OWNERS
index 0da623c..dee7d70 100644
--- a/OWNERS
+++ b/OWNERS
@@ -21,6 +21,9 @@
 nuskos@google.com
 oysteine@google.com
 
+# UI, Chromium-related metrics and simpler trace processor changes.
+altimin@google.com
+
 # Most Android-related metrics.
 ilkos@google.com