Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/python/google/protobuf/internal/descriptor_pool_test1.proto

-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-syntax = "proto2";
-
-package google.protobuf.python.internal;
-
-
-message DescriptorPoolTest1 {
-  extensions 1000 to max;
-
-  enum NestedEnum {
-    ALPHA = 1;
-    BETA = 2;
-  }
-
-  optional NestedEnum nested_enum = 1 [default = BETA];
-
-  message NestedMessage {
-    enum NestedEnum {
-      EPSILON = 5;
-      ZETA = 6;
-    }
-    optional NestedEnum nested_enum = 1 [default = ZETA];
-    optional string nested_field = 2 [default = "beta"];
-    optional DeepNestedMessage deep_nested_message = 3;
-
-    message DeepNestedMessage {
-      enum NestedEnum {
-        ETA = 7;
-        THETA = 8;
-      }
-      optional NestedEnum nested_enum = 1 [default = ETA];
-      optional string nested_field = 2 [default = "theta"];
-    }
-  }
-
-  optional NestedMessage nested_message = 2;
-}
-
-message DescriptorPoolTest2 {
-  enum NestedEnum {
-    GAMMA = 3;
-    DELTA = 4;
-  }
-
-  optional NestedEnum nested_enum = 1 [default = GAMMA];
-
-  message NestedMessage {
-    enum NestedEnum {
-      IOTA = 9;
-      KAPPA = 10;
-    }
-    optional NestedEnum nested_enum = 1 [default = IOTA];
-    optional string nested_field = 2 [default = "delta"];
-    optional DeepNestedMessage deep_nested_message = 3;
-
-    message DeepNestedMessage {
-      enum NestedEnum {
-        LAMBDA = 11;
-        MU = 12;
-      }
-      optional NestedEnum nested_enum = 1 [default = MU];
-      optional string nested_field = 2 [default = "lambda"];
-    }
-  }
-
-  optional NestedMessage nested_message = 2;
-}