Add possibility to ignore unregistered crash keys. Use this from WebView

base/debug/crash_logging_unittest.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/debug/crash_logging.h"
 
 #include <stddef.h>
 
 #include <map>
 #include <string>
@@ skipping 165 matching lines @@
   EXPECT_EQ("wor", results[2]);
   EXPECT_EQ("ld",  results[3]);
 }
 
 TEST_F(CrashLoggingTest, ChunkRounding) {
   // If max_length=12 and max_chunk_length=5, there should be 3 chunks,
   // not 2.
   base::debug::CrashKey key = { "round", 12 };
   EXPECT_EQ(3u, base::debug::InitCrashKeys(&key, 1, 5));
 }
+
+TEST_F(CrashLoggingTest, IgnoreUnregisteredKeys) {
+  base::debug::CrashKey key1 = {"first", 10};
+  base::debug::CrashKey key2 = {"second", 10};
+  base::debug::CrashKey key3 = {"third", 10};
+  base::debug::CrashKey unregistered_key = {"unreg", 10};
+  base::debug::CrashKey keys[] = {key1, key2, key3};
+  std::map<std::string, std::string>& values = *key_values_;
+
+  size_t num_keys = base::debug::InitCrashKeys(
+      keys, arraysize(keys), 10, true /* ignore_unregistered_keys */);
+
+  EXPECT_EQ(3u, num_keys);
+
+  base::debug::SetCrashKeyValue(key1.key_name, "foo");
+  base::debug::SetCrashKeyValue(key2.key_name, "bar");
+  base::debug::SetCrashKeyValue(unregistered_key.key_name, "baro");
+  EXPECT_EQ(2u, values.size());
+  EXPECT_EQ("foo", values[key1.key_name]);
+  EXPECT_EQ("bar", values[key2.key_name]);
+  EXPECT_TRUE(values.end() == values.find(unregistered_key.key_name));
+
+  base::debug::SetCrashKeyValue(key3.key_name, "yup");
+  EXPECT_EQ(3u, values.size());
+  EXPECT_EQ("yup", values[key3.key_name]);
+}