Delete Enterprise.ExistingInstallAttributesLock

Delete the Enterprise.ExistingInstallAttributesLock UMA histogram. It's
expired a while ago and doesn't seem to be needed anymore.

Bug: 1084091
Change-Id: Ie62a2f3edae5d1084f0747ef0dc2e19f9c337d0b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2548625
Auto-Submit: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Igor <igorcov@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Commit-Queue: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831965}

chromeos/tpm/install_attributes.cc

@@ -62,13 +62,6 @@ void WarnIfNonempty(const std::map<std::string, std::string>& map,
   }
 }
 
-// Reports the metric for whether the locking succeeded with existing locked
-// attributes equal to the requested ones.
-void ReportExistingLockUma(bool is_existing_lock) {
-  UMA_HISTOGRAM_BOOLEAN("Enterprise.ExistingInstallAttributesLock",
-                        is_existing_lock);
-}
-
 }  // namespace
 
 // static
@@ -262,7 +255,6 @@ void InstallAttributes::LockDevice(policy::DeviceMode device_mode,
     }
 
     // Already locked in the right mode, signal success.
-    ReportExistingLockUma(true /* is_existing_lock */);
     std::move(callback).Run(LOCK_SUCCESS);
     return;
   }
@@ -367,7 +359,6 @@ void InstallAttributes::OnReadImmutableAttributes(policy::DeviceMode mode,
     return;
   }
 
-  ReportExistingLockUma(false /* is_existing_lock */);
   std::move(callback).Run(LOCK_SUCCESS);
 }
 

chromeos/tpm/install_attributes_unittest.cc

@@ -97,53 +97,33 @@ class InstallAttributesTest : public testing::Test {
 };
 
 TEST_F(InstallAttributesTest, Lock) {
-  {
-    base::HistogramTester histogram_tester;
-    EXPECT_EQ(
-        InstallAttributes::LOCK_SUCCESS,
-        LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE, kTestDomain,
-                                   std::string(),  // realm
-                                   kTestDeviceId));
-    histogram_tester.ExpectUniqueSample(
-        "Enterprise.ExistingInstallAttributesLock", 0, 1);
-  }
+  EXPECT_EQ(
+      InstallAttributes::LOCK_SUCCESS,
+      LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE, kTestDomain,
+                                 std::string(),  // realm
+                                 kTestDeviceId));
 
-  {
-    // Locking an already locked device should succeed if the parameters match.
-    base::HistogramTester histogram_tester;
-    EXPECT_EQ(
-        InstallAttributes::LOCK_SUCCESS,
-        LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE, kTestDomain,
-                                   std::string(),  // realm
-                                   kTestDeviceId));
-    histogram_tester.ExpectUniqueSample(
-        "Enterprise.ExistingInstallAttributesLock", 1, 1);
-  }
+  // Locking an already locked device should succeed if the parameters match.
+  EXPECT_EQ(
+      InstallAttributes::LOCK_SUCCESS,
+      LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE, kTestDomain,
+                                 std::string(),  // realm
+                                 kTestDeviceId));
 
-  {
-    // But another domain should fail.
-    base::HistogramTester histogram_tester;
-    EXPECT_EQ(InstallAttributes::LOCK_WRONG_DOMAIN,
-              LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE,
-                                         "anotherexample.com",
-                                         std::string(),  // realm
-                                         kTestDeviceId));
-    histogram_tester.ExpectTotalCount(
-        "Enterprise.ExistingInstallAttributesLock", 0);
-  }
+  // But another domain should fail.
+  EXPECT_EQ(InstallAttributes::LOCK_WRONG_DOMAIN,
+            LockDeviceAndWaitForResult(policy::DEVICE_MODE_ENTERPRISE,
+                                       "anotherexample.com",
+                                       std::string(),  // realm
+                                       kTestDeviceId));
 
-  {
-    // A non-matching mode should fail as well.
-    base::HistogramTester histogram_tester;
-    EXPECT_EQ(InstallAttributes::LOCK_WRONG_MODE,
-              LockDeviceAndWaitForResult(
-                  policy::DEVICE_MODE_CONSUMER_KIOSK_AUTOLAUNCH,
-                  std::string(),    // domain
-                  std::string(),    // realm
-                  std::string()));  // device id
-    histogram_tester.ExpectTotalCount(
-        "Enterprise.ExistingInstallAttributesLock", 0);
-  }
+  // A non-matching mode should fail as well.
+  EXPECT_EQ(
+      InstallAttributes::LOCK_WRONG_MODE,
+      LockDeviceAndWaitForResult(policy::DEVICE_MODE_CONSUMER_KIOSK_AUTOLAUNCH,
+                                 std::string(),    // domain
+                                 std::string(),    // realm
+                                 std::string()));  // device id
 }
 
 TEST_F(InstallAttributesTest, IsEnterpriseManagedCloud) {

tools/metrics/histograms/histograms_xml/enterprise/histograms.xml

@@ -652,6 +652,9 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 <histogram name="Enterprise.ExistingInstallAttributesLock"
     enum="EnterpriseExistingInstallAttributesLockType"
     expires_after="2020-07-01">
+  <obsolete>
+    Removed 2020/11.
+  </obsolete>
   <owner>emaxx@chromium.org</owner>
   <owner>poromov@chromium.org</owner>
   <owner>rsorokin@chromium.org</owner>