Rename platform to header.

compiler/frontend.java/src/org/jetbrains/kotlin/load/kotlin/PackagePartClassUtils.kt

@@ -73,7 +73,7 @@ object PackagePartClassUtils {
                 (it is KtProperty ||
                 it is KtNamedFunction ||
                 it is KtScript ||
-                it is KtTypeAlias) && !it.hasModifier(KtTokens.PLATFORM_KEYWORD)
+                it is KtTypeAlias) && !it.hasModifier(KtTokens.HEADER_KEYWORD)
             }
 
     @JvmStatic fun getFilePartShortName(fileName: String): String =

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/platform/JvmPlatformConfigurator.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.platform.JavaToKotlinClassMap
 import org.jetbrains.kotlin.resolve.PlatformConfigurator
 import org.jetbrains.kotlin.resolve.calls.checkers.ReifiedTypeParameterSubstitutionChecker
 import org.jetbrains.kotlin.resolve.checkers.MissingDependencyClassChecker
-import org.jetbrains.kotlin.resolve.checkers.PlatformImplDeclarationChecker
+import org.jetbrains.kotlin.resolve.checkers.HeaderImplDeclarationChecker
 import org.jetbrains.kotlin.resolve.jvm.JvmOverloadFilter
 import org.jetbrains.kotlin.resolve.jvm.JvmTypeSpecificityComparator
 import org.jetbrains.kotlin.resolve.jvm.RuntimeAssertionsTypeChecker
@@ -47,7 +47,7 @@ object JvmPlatformConfigurator : PlatformConfigurator(
                 JvmSyntheticApplicabilityChecker(),
                 StrictfpApplicabilityChecker(),
                 AdditionalBuiltInsMemberOverrideDeclarationChecker,
-                PlatformImplDeclarationChecker()
+                HeaderImplDeclarationChecker()
         ),
 
         additionalCallCheckers = listOf(

compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaSyntheticPropertiesScope.kt

@@ -280,7 +280,7 @@ class JavaSyntheticPropertiesScope(storageManager: StorageManager, private val l
             source: SourceElement
     ) : SyntheticJavaPropertyDescriptor, PropertyDescriptorImpl(
             containingDeclaration, original, annotations, modality, visibility, isVar, name, kind, source,
-            /* lateInit = */ false, /* isConst = */ false, /* isPlatform = */ false, /* isImpl = */ false, /* isExternal = */ false
+            /* lateInit = */ false, /* isConst = */ false, /* isHeader = */ false, /* isImpl = */ false, /* isExternal = */ false
     ) {
 
         override var getMethod: FunctionDescriptor by Delegates.notNull()