diff --git a/test/mjsunit/tools/logreader.js b/test/mjsunit/tools/logreader.js
index 8b74789517..485990eaa1 100644
--- a/test/mjsunit/tools/logreader.js
+++ b/test/mjsunit/tools/logreader.js
@@ -80,19 +80,3 @@
   assertEquals('bbbbaaaa', reader.expandBackRef_('bbbb#2:4'));
   assertEquals('"#1:1"', reader.expandBackRef_('"#1:1"'));
 })();
-
-
-// See http://code.google.com/p/v8/issues/detail?id=420
-(function testReadingTruncatedLog() {
-  // Having an incorrect event in the middle of a log should throw an exception.
-  var reader1 = new devtools.profiler.LogReader({});
-  assertThrows(function() {
-    reader1.processLogChunk('alias,a,b\nxxxx\nalias,c,d\n');
-  });
-
-  // But having it as the last record should not.
-  var reader2 = new devtools.profiler.LogReader({});
-  assertDoesNotThrow(function() {
-    reader2.processLogChunk('alias,a,b\nalias,c,d\nxxxx');
-  });
-})();
diff --git a/test/mjsunit/tools/tickprocessor.js b/test/mjsunit/tools/tickprocessor.js
index abcde897ec..30b0ec23f9 100644
--- a/test/mjsunit/tools/tickprocessor.js
+++ b/test/mjsunit/tools/tickprocessor.js
@@ -379,9 +379,7 @@ function driveTickProcessorTest(
   var tp = new TickProcessor(
       new CppEntriesProviderMock(), separateIc, ignoreUnknown, stateFilter);
   var pm = new PrintMonitor(testsPath + refOutput);
-  tp.processLogFile(testsPath + logInput);
-  // Hack file name to avoid dealing with platform specifics.
-  tp.lastLogFileName_ = 'v8.log';
+  tp.processLogFileInTest(testsPath + logInput);
   tp.printStatistics();
   pm.finish();
 };
diff --git a/tools/tickprocessor.js b/tools/tickprocessor.js
index a40d95d29f..a3e14c3ae5 100644
--- a/tools/tickprocessor.js
+++ b/tools/tickprocessor.js
@@ -269,6 +269,14 @@ TickProcessor.prototype.processLogFile = function(fileName) {
 };
 
 
+TickProcessor.prototype.processLogFileInTest = function(fileName) {
+   // Hack file name to avoid dealing with platform specifics.
+  this.lastLogFileName_ = 'v8.log';
+  var contents = readFile(fileName);
+  this.processLogChunk(contents);
+};
+
+
 TickProcessor.prototype.processSharedLibrary = function(
     name, startAddr, endAddr) {
   var entry = this.profile_.addLibrary(name, startAddr, endAddr);