Make the isRunningOnBot getter more robust. (flutter#14811)

tvolkert · web-flow · commit 37ffb2d7304c · 2018-02-21T15:01:46.000-08:00
It was failing in the case of an AppContext being in scope
but not having a `BotDetector` seeded in it.
diff --git a/packages/flutter_tools/lib/src/base/utils.dart b/packages/flutter_tools/lib/src/base/utils.dart
@@ -45,10 +45,8 @@ class BotDetector {
 }
 
 bool get isRunningOnBot {
-  if (context == null) {
-    return _kBotDetector.isRunningOnBot;
-  }
-  return context[BotDetector].isRunningOnBot;
+  final BotDetector botDetector = context?.getVariable(BotDetector) ?? _kBotDetector;
+  return botDetector.isRunningOnBot;
 }
 
 String hex(List<int> bytes) {

Original file line number	Diff line number	Diff line change
`@@ -45,10 +45,8 @@ class BotDetector {`
`45`	`45`	`}`
`46`	`46`
`47`	`47`	`bool get isRunningOnBot {`
`48`		`- if (context == null) {`
`49`		`- return _kBotDetector.isRunningOnBot;`
`50`		`- }`
`51`		`- return context[BotDetector].isRunningOnBot;`
	`48`	`+ final BotDetector botDetector = context?.getVariable(BotDetector) ?? _kBotDetector;`
	`49`	`+ return botDetector.isRunningOnBot;`
`52`	`50`	`}`
`53`	`51`
`54`	`52`	`String hex(List<int> bytes) {`