introduce highest registered level to be used in tests

+ fix sentence case IDEA-CR-31331

java/java-psi-api/src/com/intellij/pom/java/LanguageLevel.java

@@ -10,6 +10,7 @@ import com.intellij.util.lang.JavaVersion;
 import org.jetbrains.annotations.Nls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.TestOnly;
 
 /**
  * Represents a language level (i.e. features available) of a Java code.
@@ -46,6 +47,12 @@ public enum LanguageLevel {
     return this == JDK_X ? "Java X" :  "Java " + JavaSdkVersion.fromLanguageLevel(this).getDescription();
   }
 
+  @TestOnly
+  public static LanguageLevel getHighestRegistered() {
+    LanguageLevel[] values = values();
+    return values[values.length - 1];
+  }
+  
   @NotNull
   @Nls
   public String getPresentableText() {

java/java-psi-api/src/messages/JavaCoreBundle.properties

@@ -9,5 +9,5 @@ jdk.1.7.language.level.description=7 - Diamonds, ARM, multi-catch etc.
 jdk.1.8.language.level.description=8 - Lambdas, type annotations etc.
 jdk.1.9.language.level.description=9 - Modules, private methods in interfaces etc.
 jdk.10.language.level.description=10 - Local variable type inference
-jdk.11.language.level.description=11 - Local-Variable Syntax for Lambda Parameters
+jdk.11.language.level.description=11 - Local-variable syntax for lambda parameters
 jdk.X.language.level.description=X - Experimental features

java/java-tests/testSrc/com/intellij/java/parser/JavaParsingTestCase.java

@@ -57,7 +57,7 @@ public abstract class JavaParsingTestCase extends ParsingTestCase {
   }
 
   protected LanguageLevel getHighestLanguageLevel() {
-    return LanguageLevel.HIGHEST;
+    return LanguageLevel.getHighestRegistered();
   }
 
   @Override

java/java-tests/testSrc/com/intellij/java/parser/partial/ExpressionParserTest.java

@@ -3,7 +3,6 @@ package com.intellij.java.parser.partial;
 
 import com.intellij.java.parser.JavaParsingTestCase;
 import com.intellij.lang.java.parser.JavaParser;
-import com.intellij.pom.java.LanguageLevel;
 
 public class ExpressionParserTest extends JavaParsingTestCase {
   public ExpressionParserTest() {
@@ -145,11 +144,6 @@ public class ExpressionParserTest extends JavaParsingTestCase {
   public void testLambdaExpression26() { doParserTest("(var var) -> var"); }
   public void testAmbiguousLambdaExpression() { doParserTest("f( (x) < y , z > (w) -> v )"); }
 
-  @Override
-  protected LanguageLevel getHighestLanguageLevel() {
-    return LanguageLevel.JDK_11;
-  }
-
   private void doParserTest(String text) {
     doParserTest(text, builder -> JavaParser.INSTANCE.getExpressionParser().parse(builder));
   }

java/java-tests/testSrc/com/intellij/java/parser/partial/ReferenceParserTest.java

@@ -4,7 +4,6 @@ package com.intellij.java.parser.partial;
 import com.intellij.java.parser.JavaParsingTestCase;
 import com.intellij.lang.java.parser.JavaParser;
 import com.intellij.lang.java.parser.ReferenceParser;
-import com.intellij.pom.java.LanguageLevel;
 
 public class ReferenceParserTest extends JavaParsingTestCase {
   public ReferenceParserTest() {
@@ -40,11 +39,6 @@ public class ReferenceParserTest extends JavaParsingTestCase {
   public void testAnyTypeParams() { doTypeParamsParserTest("<any T>"); }
   public void testAnyTypeArgs() { doTypeParserTest("T<E_SRC, any, E_DST, ?>"); }
 
-  @Override
-  protected LanguageLevel getHighestLanguageLevel() {
-    return LanguageLevel.JDK_X;
-  }
-
   private void doRefParserTest(String text, boolean incomplete) {
     doParserTest(text, builder -> JavaParser.INSTANCE.getReferenceParser().parseJavaCodeReference(builder, incomplete, false, false, false));
   }

java/java-tests/testSrc/com/intellij/java/psi/formatter/java/JavaFormatterSpaceTest.java

@@ -16,7 +16,7 @@ public class JavaFormatterSpaceTest extends AbstractJavaFormatterTest {
   @Override
   protected void setUp() throws Exception {
     super.setUp();
-    LanguageLevelProjectExtension.getInstance(LightPlatformTestCase.getProject()).setLanguageLevel(LanguageLevel.HIGHEST);
+    LanguageLevelProjectExtension.getInstance(LightPlatformTestCase.getProject()).setLanguageLevel(LanguageLevel.getHighestRegistered());
   }
 
   public void testSpacingBetweenTypeParameters() {