Option support for `enableGenericMethods`.

pkg/analyzer/lib/src/context/context.dart

Index: pkg/analyzer/lib/src/context/context.dart
diff --git a/pkg/analyzer/lib/src/context/context.dart b/pkg/analyzer/lib/src/context/context.dart
index d1fa70ea49200cdd973812b80dc5867487013f32..feb1f789bf7b33a5aef62633e8e0dc2a23a00f0f 100644
--- a/pkg/analyzer/lib/src/context/context.dart
+++ b/pkg/analyzer/lib/src/context/context.dart
@@ -265,6 +265,7 @@ class AnalysisContextImpl implements InternalAnalysisContext {
         this._options.strongMode != options.strongMode ||
         this._options.enableStrictCallChecks !=
             options.enableStrictCallChecks ||
+        this._options.enableGenericMethods != options.enableGenericMethods ||
         this._options.enableSuperMixins != options.enableSuperMixins;
     int cacheSize = options.cacheSize;
     if (this._options.cacheSize != cacheSize) {
@@ -275,6 +276,7 @@ class AnalysisContextImpl implements InternalAnalysisContext {
     this._options.generateImplicitErrors = options.generateImplicitErrors;
     this._options.generateSdkErrors = options.generateSdkErrors;
     this._options.dart2jsHint = options.dart2jsHint;
+    this._options.enableGenericMethods = options.enableGenericMethods;
     this._options.enableStrictCallChecks = options.enableStrictCallChecks;
     this._options.enableSuperMixins = options.enableSuperMixins;
     this._options.hint = options.hint;