Added language feature check for inline properties

compiler/frontend/src/org/jetbrains/kotlin/config/LanguageFeatureSettings.kt

@@ -27,6 +27,7 @@ enum class LanguageFeature(val sinceVersion: LanguageVersion) {
     Coroutines(KOTLIN_1_1),
     AdditionalBuiltInsMembers(KOTLIN_1_1),
     DataClassInheritance(KOTLIN_1_1),
+    InlineProperties(KOTLIN_1_1)
     ;
 
     companion object {

compiler/frontend/src/org/jetbrains/kotlin/resolve/ModifiersChecker.kt

@@ -94,7 +94,8 @@ object ModifierCheckerCore {
 
     val featureDependencies = mapOf(
             COROUTINE_KEYWORD to LanguageFeature.Coroutines,
-            SUSPEND_KEYWORD   to LanguageFeature.Coroutines
+            SUSPEND_KEYWORD   to LanguageFeature.Coroutines,
+            INLINE_KEYWORD   to LanguageFeature.InlineProperties
     )
 
     // NOTE: deprecated targets must be possible!
@@ -252,12 +253,17 @@ object ModifierCheckerCore {
     private fun checkLanguageLevelSupport(
             trace: BindingTrace,
             node: ASTNode,
-            languageFeatureSettings: LanguageFeatureSettings
+            languageFeatureSettings: LanguageFeatureSettings,
+            actualTargets: List<KotlinTarget>
     ): Boolean {
         val modifier = node.elementType as KtModifierKeywordToken
+
         val dependency = featureDependencies[modifier] ?: return true
 
         if (!languageFeatureSettings.supportsFeature(dependency)) {
+            if (dependency == LanguageFeature.InlineProperties && actualTargets.size == 1 && actualTargets.contains(FUNCTION)) {
+                return true
+            }
             trace.report(Errors.UNSUPPORTED_FEATURE.on(node.psi, dependency))
             return false
         }
@@ -313,7 +319,7 @@ object ModifierCheckerCore {
                 else if (!checkParent(trace, second, parentDescriptor)) {
                     incorrectNodes += second
                 }
-                else if (!checkLanguageLevelSupport(trace, second, languageFeatureSettings)) {
+                else if (!checkLanguageLevelSupport(trace, second, languageFeatureSettings, actualTargets)) {
                     incorrectNodes += second
                 }
             }

compiler/testData/diagnostics/tests/sourceCompatibility/noInlineProperty.kt

@@ -0,0 +1,11 @@
+// !LANGUAGE: -InlineProperties
+var value: Int = 0
+
+<!UNSUPPORTED_FEATURE!>inline<!> var z: Int
+    get() = ++value
+    set(p: Int) { value = p }
+
+
+var z2: Int
+    <!UNSUPPORTED_FEATURE!>inline<!> get() = ++value
+    <!UNSUPPORTED_FEATURE!>inline<!> set(p: Int) { value = p }

compiler/testData/diagnostics/tests/sourceCompatibility/noInlineProperty.txt

@@ -0,0 +1,5 @@
+package
+
+public var value: kotlin.Int
+public var z: kotlin.Int
+public var z2: kotlin.Int

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -18660,6 +18660,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("noInlineProperty.kt")
+            public void testNoInlineProperty() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/sourceCompatibility/noInlineProperty.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("noLocalDelegatedProperty.kt")
             public void testNoLocalDelegatedProperty() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/sourceCompatibility/noLocalDelegatedProperty.kt");