Fixes some memory leaks in //runtime/bin

runtime/bin/process.cc

Index: runtime/bin/process.cc
diff --git a/runtime/bin/process.cc b/runtime/bin/process.cc
index b58304952cd4193e4ffcb88bbc0b5bd19a35c419..9c9ed94e7574c3b8c6f101b1c383bb9fccd7723a 100644
--- a/runtime/bin/process.cc
+++ b/runtime/bin/process.cc
@@ -151,7 +151,7 @@ void FUNCTION_NAME(Process_Start)(Dart_NativeArguments args) {
   Dart_Handle stderr_handle = Dart_GetNativeArgument(args, 8);
   Dart_Handle exit_handle = Dart_GetNativeArgument(args, 9);
   intptr_t pid = -1;
-  char* os_error_message = NULL;
+  char* os_error_message = NULL;  // Scope allocated by Process::Start.
 
   int error_code = Process::Start(path,
                                   string_args,
@@ -190,13 +190,11 @@ void FUNCTION_NAME(Process_Start)(Dart_NativeArguments args) {
     if (Dart_IsError(result)) {
       delete[] string_args;
       delete[] string_environment;
-      free(os_error_message);
       Dart_PropagateError(result);
     }
   }
   delete[] string_args;
   delete[] string_environment;
-  free(os_error_message);
   Dart_SetReturnValue(args, Dart_NewBoolean(error_code == 0));
 }
 
@@ -323,25 +321,24 @@ void FUNCTION_NAME(SystemEncodingToString)(Dart_NativeArguments args) {
   Dart_Handle bytes = Dart_GetNativeArgument(args, 0);
   intptr_t bytes_length = 0;
   Dart_Handle result = Dart_ListLength(bytes, &bytes_length);
-  if (Dart_IsError(result)) Dart_PropagateError(result);
-  uint8_t* buffer =
-      reinterpret_cast<uint8_t*>(Dart_ScopeAllocate(bytes_length + 1));
+  if (Dart_IsError(result)) {
+    Dart_PropagateError(result);
+  }
+  uint8_t* buffer = Dart_ScopeAllocate(bytes_length + 1);
   result = Dart_ListGetAsBytes(bytes, 0, buffer, bytes_length);
   buffer[bytes_length] = '\0';
-  if (Dart_IsError(result)) Dart_PropagateError(result);
+  if (Dart_IsError(result)) {
+    Dart_PropagateError(result);
+  }
   intptr_t len;
-  char* str =
-      StringUtils::ConsoleStringToUtf8(
-          reinterpret_cast<char*>(buffer),
-          bytes_length,
-          &len);
+  char* str = StringUtils::ConsoleStringToUtf8(
+      reinterpret_cast<char*>(buffer), bytes_length, &len);
   if (str == NULL) {
     Dart_ThrowException(
         DartUtils::NewInternalError("SystemEncodingToString failed"));
   }
   result =
       Dart_NewStringFromUTF8(reinterpret_cast<const uint8_t*>(str), len);
-  free(str);
   Dart_SetReturnValue(args, result);
 }
 
@@ -368,7 +365,6 @@ void FUNCTION_NAME(StringToSystemEncoding)(Dart_NativeArguments args) {
     memmove(buffer, system_string, system_len);
   }
   Dart_SetReturnValue(args, external_array);
-  free(const_cast<char*>(system_string));
 }
 
 }  // namespace bin