Disable the GoogleTestSecurityManager by default

and explicitly enable it for tests that rely on it.

The SecurityManager is being permanently disabled in JDK 24, see https://openjdk.org/jeps/486

PiperOrigin-RevId: 696974212
Change-Id: I425c0bb66e0c1c057129712e45b60ba481971db8
diff --git a/src/java_tools/junitrunner/java/com/google/testing/junit/runner/junit4/JUnit4Config.java b/src/java_tools/junitrunner/java/com/google/testing/junit/runner/junit4/JUnit4Config.java
index 21bd785..8d2b883 100644
--- a/src/java_tools/junitrunner/java/com/google/testing/junit/runner/junit4/JUnit4Config.java
+++ b/src/java_tools/junitrunner/java/com/google/testing/junit/runner/junit4/JUnit4Config.java
@@ -90,7 +90,7 @@
       return false; // Don't install over the specified security manager
     }
     return Boolean.valueOf(
-        systemProperties.getProperty(SHOULD_INSTALL_SECURITY_MANAGER_PROPERTY, "true"));
+        systemProperties.getProperty(SHOULD_INSTALL_SECURITY_MANAGER_PROPERTY, "false"));
   }
 
   /**
diff --git a/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4ConfigTest.java b/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4ConfigTest.java
index 8357ea3e..f7e8ede 100644
--- a/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4ConfigTest.java
+++ b/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4ConfigTest.java
@@ -85,7 +85,7 @@
     GoogleTestSecurityManager.uninstallIfInstalled();
 
     JUnit4Config config = createConfigWithProperties(new Properties());
-    assertThat(config.shouldInstallSecurityManager()).isTrue();
+    assertThat(config.shouldInstallSecurityManager()).isFalse();
   }
 
   @Test
diff --git a/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4RunnerTest.java b/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4RunnerTest.java
index e82c27d..dcdd3f9 100644
--- a/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4RunnerTest.java
+++ b/src/java_tools/junitrunner/javatests/com/google/testing/junit/runner/junit4/JUnit4RunnerTest.java
@@ -444,8 +444,8 @@
       String apiVersion, boolean shouldInstallSecurityManager) {
     Properties properties = new Properties();
     properties.setProperty(JUnit4Config.JUNIT_API_VERSION_PROPERTY, apiVersion);
-    if (!shouldInstallSecurityManager) {
-      properties.setProperty("java.security.manager", "whatever");
+    if (shouldInstallSecurityManager) {
+      properties.setProperty(JUnit4Config.SHOULD_INSTALL_SECURITY_MANAGER_PROPERTY, "true");
     }
     return properties;
   }