[java] Fix NPE regression in 4.8.0 (#11701)

Author: Kouzukii

java/src/org/openqa/selenium/grid/node/config/SessionCapabilitiesMutator.java

@@ -57,6 +57,9 @@ public Capabilities apply(Capabilities capabilities) {
     }
 
     String browserName = capabilities.getBrowserName().toLowerCase();
+    if (!BROWSER_OPTIONS.containsKey(browserName)) {
+      return capabilities;
+    }
     String options = BROWSER_OPTIONS.get(browserName);
     if (slotStereotype.asMap().containsKey(options) && capabilities.asMap().containsKey(options)) {
 

java/test/org/openqa/selenium/grid/node/config/SessionCapabilitiesMutatorTest.java

@@ -289,4 +289,19 @@ void shouldMergeTopLevelStereotypeAndCaps() {
     assertThat(modifiedCapabilities.get("unhandledPromptBehavior")).isEqualTo("accept");
     assertThat(modifiedCapabilities.get("pageLoadStrategy")).isEqualTo("normal");
   }
+
+  @Test
+  void shouldAllowUnknownBrowserNames() {
+    stereotype = new ImmutableCapabilities(
+            "browserName", "safari");
+
+    sessionCapabilitiesMutator = new SessionCapabilitiesMutator(stereotype);
+
+    capabilities = new ImmutableCapabilities(
+            "browserName", "safari");
+
+    Map<String, Object> modifiedCapabilities = sessionCapabilitiesMutator.apply(capabilities).asMap();
+
+    assertThat(modifiedCapabilities.get("browserName")).isEqualTo("safari");
+  }
 }