Bug 123786 Following bug 109980, the compliance 6.0 should be added to the compiler's compliance list.
If the JRE/JDK used is a 1.6/6.0 VM, then the compliance 6.0 should be available. Compliance 1.6 implies source level 1.6 and target level 1.6.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/ComplianceConfigurationBlock.java
private static final Key PREF_CODEGEN_INLINE_JSR_BYTECODE= getJDTCoreKey(JavaCore.COMPILER_CODEGEN_INLINE_JSR_BYTECODE);
	
	private static final Key PREF_SOURCE_COMPATIBILITY= getJDTCoreKey(JavaCore.COMPILER_SOURCE);
	private static final Key PREF_COMPLIANCE= getJDTCoreKey(JavaCore.COMPILER_COMPLIANCE);
	private static final Key PREF_PB_ASSERT_AS_IDENTIFIER= getJDTCoreKey(JavaCore.COMPILER_PB_ASSERT_IDENTIFIER);
	private static final Key PREF_PB_ENUM_AS_IDENTIFIER= getJDTCoreKey(JavaCore.COMPILER_PB_ENUM_IDENTIFIER);
	
	private static final Key INTR_DEFAULT_COMPLIANCE= getJDTUIKey("internal.default.compliance"); 
	
	private static final String GENERATE= JavaCore.GENERATE;
	private static final String DO_NOT_GENERATE= JavaCore.DO_NOT_GENERATE;
	
	private static final String PRESERVE= JavaCore.PRESERVE;
	private static final String OPTIMIZE_OUT= JavaCore.OPTIMIZE_OUT;
	
	private static final String VERSION_1_1= JavaCore.VERSION_1_1;
	private static final String VERSION_1_2= JavaCore.VERSION_1_2;
	private static final String VERSION_1_3= JavaCore.VERSION_1_3;
	private static final String VERSION_1_4= JavaCore.VERSION_1_4;
	private static final String VERSION_1_5= JavaCore.VERSION_1_5;
	
	private static final String ERROR= JavaCore.ERROR;
	private static final String WARNING= JavaCore.WARNING;
	private static final String IGNORE= JavaCore.IGNORE;
	private static final String ENABLED= JavaCore.ENABLED;
	private static final String DISABLED= JavaCore.DISABLED;
	
	
	private static final String DEFAULT_CONF= "default"; 
	private static final String USER_CONF= "user";