Revert "Support passing an environment variable map to child processes."

runtime/bin/process_impl.dart

Index: runtime/bin/process_impl.dart
diff --git a/runtime/bin/process_impl.dart b/runtime/bin/process_impl.dart
index bb722500b51370f3da49b0102b8bcbcb3c9a8e57..1ff6de99539345007a73cb90a160aaaf6da46bd0 100644
--- a/runtime/bin/process_impl.dart
+++ b/runtime/bin/process_impl.dart
@@ -68,25 +68,6 @@ class _InteractiveProcess implements Process {
       }
     }
 
-    if (options !== null && options.environment !== null) {
-      var env = options.environment;
-      if (env is !Map) {
-        throw new IllegalArgumentException("Environment is not a map: $env");
-      }
-      _environment = [];
-      env.forEach((key, value) {
-        if (key is !String || value is !String) {
-          throw new IllegalArgumentException(
-              "Environment key or value is not a string: ($key, $value)");
-        }
-        if (key.contains('=')) {
-          throw new IllegalArgumentException(
-              "Environment keys may not contain '=': $key");
-        }
-        _environment.add('$key=$value');
-      });
-    }
-
     _in = new _Socket._internalReadOnly();  // stdout coming from process.
     _out = new _Socket._internalWriteOnly();  // stdin going to process.
     _err = new _Socket._internalReadOnly();  // stderr coming from process.
@@ -158,7 +139,6 @@ class _InteractiveProcess implements Process {
     bool success = _start(_path,
                           _arguments,
                           _workingDirectory,
-                          _environment,
                           _in,
                           _out,
                           _err,
@@ -212,7 +192,6 @@ class _InteractiveProcess implements Process {
   bool _start(String path,
               List<String> arguments,
               String workingDirectory,
-              List<String> environment,
               Socket input,
               Socket output,
               Socket error,
@@ -295,7 +274,6 @@ class _InteractiveProcess implements Process {
   String _path;
   ObjectArray<String> _arguments;
   String _workingDirectory;
-  List<String> _environment;
   // Private methods of _Socket are used by _in, _out, and _err.
   _Socket _in;
   _Socket _out;