Factoring GUID generation from metrics to base

Factors GUID generation into base/rand_util.  The Autofill feature is in need of this utility so am factoring GUID generation out of metrics and moving to the commons.

BUG=58813
TEST=RandUtilTest.GUIDGeneratesAllZeroes, RandUtilTest.GUIDGeneratesCorrectly, RandUtilTest.GUIDCorrectlyFormatted, MetricsServiceTest.ClientIdCorrectlyFormatted

Review URL: http://codereview.chromium.org/3800001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62480 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 7 insertions, 62 deletions

diff --git a/chrome/browser/metrics/metrics_service.cc b/chrome/browser/metrics/metrics_service.cc
index b6d4c3f..e4c9a12 100644
--- a/chrome/browser/metrics/metrics_service.cc
+++ b/chrome/browser/metrics/metrics_service.cc
@@ -158,15 +158,11 @@
 
 #include "chrome/browser/metrics/metrics_service.h"
 
-#if defined(OS_WIN)
-#include <windows.h>
-#include <objbase.h>
-#endif
-
 #include "base/base64.h"
 #include "base/command_line.h"
 #include "base/histogram.h"
 #include "base/md5.h"
+#include "base/rand_util.h"
 #include "base/string_number_conversions.h"
 #include "base/thread.h"
 #include "base/utf_string_conversions.h"
@@ -192,10 +188,6 @@
 #include "webkit/glue/plugins/webplugininfo.h"
 #include "libxml/xmlwriter.h"
 
-#if !defined(OS_WIN)
-#include "base/rand_util.h"
-#endif
-
 // TODO(port): port browser_distribution.h.
 #if !defined(OS_POSIX)
 #include "chrome/installer/util/browser_distribution.h"
@@ -816,38 +808,9 @@ void MetricsService::OnInitTaskComplete(
 }
 
 std::string MetricsService::GenerateClientID() {
-#if defined(OS_WIN)
-  const int kGUIDSize = 39;
-
-  GUID guid;
-  HRESULT guid_result = CoCreateGuid(&guid);
-  DCHECK(SUCCEEDED(guid_result));
-
-  std::wstring guid_string;
-  int result = StringFromGUID2(guid,
-                               WriteInto(&guid_string, kGUIDSize), kGUIDSize);
-  DCHECK(result == kGUIDSize);
-
-  return WideToUTF8(guid_string.substr(1, guid_string.length() - 2));
-#else
-  uint64 sixteen_bytes[2] = { base::RandUint64(), base::RandUint64() };
-  return RandomBytesToGUIDString(sixteen_bytes);
-#endif
+  return base::GenerateGUID();
 }
 
-#if defined(OS_POSIX)
-// TODO(cmasone): Once we're comfortable this works, migrate Windows code to
-// use this as well.
-std::string MetricsService::RandomBytesToGUIDString(const uint64 bytes[2]) {
-  return StringPrintf("%08X-%04X-%04X-%04X-%012llX",
-                      static_cast<unsigned int>(bytes[0] >> 32),
-                      static_cast<unsigned int>((bytes[0] >> 16) & 0x0000ffff),
-                      static_cast<unsigned int>(bytes[0] & 0x0000ffff),
-                      static_cast<unsigned int>(bytes[1] >> 48),
-                      bytes[1] & 0x0000ffffffffffffULL);
-}
-#endif
-
 //------------------------------------------------------------------------------
 // State save methods
 
diff --git a/chrome/browser/metrics/metrics_service.h b/chrome/browser/metrics/metrics_service.h
index 650935a..f1cfbb2 100644
--- a/chrome/browser/metrics/metrics_service.h
+++ b/chrome/browser/metrics/metrics_service.h
@@ -192,12 +192,6 @@ class MetricsService : public NotificationObserver,
   // Generates a new client ID to use to identify self to metrics server.
   static std::string GenerateClientID();
 
-#if defined(OS_POSIX)
-  // Generates a new client ID to use to identify self to metrics server,
-  // given 128 bits of randomness.
-  static std::string RandomBytesToGUIDString(const uint64 bytes[2]);
-#endif
-
   // Schedule the next save of LocalState information.  This is called
   // automatically by the task that performs each save to schedule the next one.
   void ScheduleNextStateSave();
diff --git a/chrome/browser/metrics/metrics_service_unittest.cc b/chrome/browser/metrics/metrics_service_unittest.cc
index a5ec080..9e7b463 100644
--- a/chrome/browser/metrics/metrics_service_unittest.cc
+++ b/chrome/browser/metrics/metrics_service_unittest.cc
@@ -13,18 +13,12 @@
 
 #include "testing/gtest/include/gtest/gtest.h"
 
-#if defined(OS_POSIX) && defined(LINUX2)
-TEST(MetricsServiceTest, ClientIdGeneratesAllZeroes) {
-  uint64 bytes[] = { 0, 0 };
-  std::string clientid = MetricsService::RandomBytesToGUIDString(bytes);
-  EXPECT_EQ("00000000-0000-0000-0000-000000000000", clientid);
-}
-TEST(MetricsServiceTest, ClientIdGeneratesCorrectly) {
-  uint64 bytes[] = { 0x0123456789ABCDEFULL, 0xFEDCBA9876543210ULL };
-  std::string clientid = MetricsService::RandomBytesToGUIDString(bytes);
-  EXPECT_EQ("01234567-89AB-CDEF-FEDC-BA9876543210", clientid);
-}
+class MetricsServiceTest : public ::testing::Test {
+};
+
+static const size_t kMaxLocalListSize = 3;
 
+// Ensure the ClientId is formatted as expected.
 TEST(MetricsServiceTest, ClientIdCorrectlyFormatted) {
   std::string clientid = MetricsService::GenerateClientID();
   EXPECT_EQ(36U, clientid.length());
@@ -38,12 +32,6 @@ TEST(MetricsServiceTest, ClientIdCorrectlyFormatted) {
     }
   }
 }
-#endif
-
-class MetricsServiceTest : public ::testing::Test {
-};
-
-static const size_t kMaxLocalListSize = 3;
 
 // Store and retrieve empty list.
 TEST(MetricsServiceTest, EmptyLogList) {