Bump SDK constraint to allow to early Dart 2.0 release (#60)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 16336e6..40a944a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+#### 2.3.4
+
+* Bumped maximum Dart SDK version to 2.0.0-dev.infinity
+
 #### 2.3.3
 
 * Relaxes version requirements on `package:intl`
diff --git a/pubspec.yaml b/pubspec.yaml
index f0505f1..d5ab8bc 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: file
-version: 2.3.3
+version: 2.3.4
 authors:
 - Matan Lurey <matanl@google.com>
 - Yegor Jbanov <yjbanov@google.com>
@@ -16,4 +16,4 @@
   test: ^0.12.18
 
 environment:
-  sdk: '>=1.19.0 <2.0.0'
+  sdk: '>=1.19.0 <2.0.0-dev.infinity'