Remove some usages of KotlinBuiltIns.getInstance()

Introduce DeclarationDescriptor.builtIns extension to get builtins where descriptors are available
Introduce various utilities in KotlinBuiltIns to check for primitive types and get fq names of builtins

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/Utils.kt

@@ -44,6 +44,7 @@ import org.jetbrains.kotlin.idea.util.FuzzyType
 import org.jetbrains.kotlin.idea.util.makeNotNullable
 import org.jetbrains.kotlin.idea.util.nullability
 import org.jetbrains.kotlin.idea.util.TypeNullability
+import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
 
 class ArtificialElementInsertHandler(
         val textBeforeCaret: String, val textAfterCaret: String, val shortenRefs: Boolean) : InsertHandler<LookupElement>{
@@ -233,10 +234,11 @@ fun functionType(function: FunctionDescriptor): JetType? {
         null
     else
         extensionReceiverType ?: memberReceiverType
-    return KotlinBuiltIns.getInstance().getFunctionType(function.getAnnotations(),
-                                                        receiverType,
-                                                        function.getValueParameters().map { it.getType() },
-                                                        function.getReturnType() ?: return null)
+    return function.builtIns.getFunctionType(
+            function.getAnnotations(), receiverType,
+            function.getValueParameters().map { it.getType() },
+            function.getReturnType() ?: return null
+    )
 }
 
 fun LookupElementFactory.createLookupElement(