perf - Fix crash in dataframe merge.

Bug: skia:
Change-Id: Id4e139e207f62484234d4ef9e155fd383e6d663c
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/199020
Auto-Submit: Joe Gregorio <jcgregorio@google.com>
Reviewed-by: Ravi Mistry <rmistry@google.com>
Commit-Queue: Ravi Mistry <rmistry@google.com>
diff --git a/perf/go/dataframe/dataframe.go b/perf/go/dataframe/dataframe.go
index f824a14..e53d8dc 100644
--- a/perf/go/dataframe/dataframe.go
+++ b/perf/go/dataframe/dataframe.go
@@ -144,6 +144,7 @@
 				aMap[i] = len(ret)
 				ret = append(ret, a[i])
 			}
+			break
 		}
 		if a[pA].Offset < b[pB].Offset {
 			aMap[pA] = len(ret)