Flutter 1.26.0-17.6.pre (#662)

diff --git a/flutter-sdk-version.yaml b/flutter-sdk-version.yaml
index d71e41e..85251bc 100644
--- a/flutter-sdk-version.yaml
+++ b/flutter-sdk-version.yaml
@@ -12,4 +12,4 @@
 
 flutter_sdk:
   # channel: beta
-  version: 1.26.0-17.5.pre
+  version: 1.26.0-17.6.pre