[Swiftify] Fix crash calling cgImage.width

cgImage.width calls the C function, CGImageGetWidth(CGImageRef).
Swift representation and Clang representation of this function
seem to have a parameter number mismatch, causing swiftify function
to crash.

rdar://149691207

Author: rapidsna

lib/ClangImporter/ImportDecl.cpp

@@ -4712,7 +4712,7 @@ namespace {
       auto loc = Impl.importSourceLoc(decl->getLocation());
       auto dc = Impl.importDeclContextOf(
           decl, importedName.getEffectiveContext());
-      
+
       SmallVector<GenericTypeParamDecl *, 4> genericParams;
       for (auto &param : *decl->getTemplateParameters()) {
         auto genericParamDecl =
@@ -5495,7 +5495,7 @@ namespace {
                                               objcClass->getDeclaredType());
       Impl.SwiftContext.evaluator.cacheOutput(ExtendedNominalRequest{result},
                                               std::move(objcClass));
-      
+
       Identifier categoryName;
       if (!decl->getName().empty())
         categoryName = Impl.SwiftContext.getIdentifier(decl->getName());
@@ -9122,6 +9122,9 @@ void ClangImporter::Implementation::swiftify(FuncDecl *MappedDecl) {
   if (!ClangDecl)
     return;
 
+  if (ClangDecl->getNumParams() != MappedDecl->getParameters()->size())
+    return;
+
   llvm::SmallString<128> MacroString;
   // We only attach the macro if it will produce an overload. Any __counted_by
   // will produce an overload, since UnsafeBufferPointer is still an improvement
@@ -9537,7 +9540,7 @@ ClangImporter::Implementation::importDeclImpl(const clang::NamedDecl *ClangDecl,
     Result = importDecl(UnderlyingDecl, version);
     SkippedOverTypedef = true;
   }
-  
+
   if (!Result) {
     SwiftDeclConverter converter(*this, version);
     Result = converter.Visit(ClangDecl);

test/Interop/ObjC/swiftify-import/getter.swift

@@ -0,0 +1,20 @@
+// REQUIRES: swift_feature_SafeInteropWrappers
+
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: %target-swift-ide-test -plugin-path %swift-plugin-dir -I %t/Inputs -enable-experimental-feature SafeInteropWrappers -print-module -module-to-print=Method -source-filename=x
+// RUN: %target-swift-frontend -plugin-path %swift-plugin-dir -I %t/Inputs -enable-experimental-feature SafeInteropWrappers %t/method.swift -dump-macro-expansions -typecheck -verify
+
+// REQUIRES: objc_interop
+
+//--- Inputs/module.modulemap
+module Method {
+    header "method.h"
+}
+
+//--- method.swift
+import CoreImage
+
+func test(_ image: CGImage) -> Int {
+  return image.width
+}