Simplify how patch files are specified to analyzer.

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 0faff27f7977cbabc80e997fa9a92e635bce255d..f5c554cae78a8cd7bb694e83b7428b6e7015640f 100644
--- a/pkg/analyzer/lib/src/context/context.dart
+++ b/pkg/analyzer/lib/src/context/context.dart
@@ -300,7 +300,7 @@ class AnalysisContextImpl implements InternalAnalysisContext {
         this._options.enableStrictCallChecks !=
             options.enableStrictCallChecks ||
         this._options.enableSuperMixins != options.enableSuperMixins ||
-        this._options.patchPlatform != options.patchPlatform;
+        !_samePatchPaths(this._options.patchPaths, options.patchPaths);
     this._options.analyzeFunctionBodiesPredicate =
         options.analyzeFunctionBodiesPredicate;
     this._options.generateImplicitErrors = options.generateImplicitErrors;
@@ -328,7 +328,7 @@ class AnalysisContextImpl implements InternalAnalysisContext {
     this._options.trackCacheDependencies = options.trackCacheDependencies;
     this._options.disableCacheFlushing = options.disableCacheFlushing;
     this._options.finerGrainedInvalidation = options.finerGrainedInvalidation;
-    this._options.patchPlatform = options.patchPlatform;
+    this._options.patchPaths = options.patchPaths;
     if (options is AnalysisOptionsImpl) {
       this._options.strongModeHints = options.strongModeHints;
       this._options.implicitCasts = options.implicitCasts;
@@ -1966,6 +1966,21 @@ class AnalysisContextImpl implements InternalAnalysisContext {
       return true;
     });
   }
+
+  static bool _samePatchPaths(
+      Map<String, List<String>> a, Map<String, List<String>> b) {
+    if (a.length != b.length) return false;
+    for (var key in a.keys) {
+      if (!b.containsKey(key)) return false;
+      var aValue = a[key];
+      var bValue = b[key];
+      if (aValue.length != bValue.length) return false;
+      for (var i = 0; i < aValue.length; i++) {
+        if (aValue[i] != bValue[i]) return false;
+      }
+    }
+    return true;
+  }
 }
 
 /**