mac: Expose keychain access frequency to Telemetry.

crypto/mock_apple_keychain.cc

Index: crypto/mock_apple_keychain.cc
diff --git a/crypto/mock_apple_keychain.cc b/crypto/mock_apple_keychain.cc
index 1ddfc8679461c6fddf320642405dc31f98643c0b..ce0bc4f8b35010afccf74c53498088d54a63c185 100644
--- a/crypto/mock_apple_keychain.cc
+++ b/crypto/mock_apple_keychain.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/logging.h"
+#include "base/mac/keychain_metrics.h"
 #include "base/time/time.h"
 #include "crypto/mock_apple_keychain.h"
 
@@ -17,6 +18,8 @@ OSStatus MockAppleKeychain::FindGenericPassword(
     UInt32* passwordLength,
     void** passwordData,
     SecKeychainItemRef* itemRef) const {
+  base::mac::IncrementKeychainAccessHistogram();
+
   // When simulating |noErr|, return canned |passwordData| and
   // |passwordLength|.  Otherwise, just return given code.
   if (find_generic_result_ == noErr) {
@@ -48,6 +51,8 @@ OSStatus MockAppleKeychain::AddGenericPassword(
     UInt32 passwordLength,
     const void* passwordData,
     SecKeychainItemRef* itemRef) const {
+  base::mac::IncrementKeychainAccessHistogram();
+
   called_add_generic_ = true;
 
   DCHECK_GT(passwordLength, 0U);