Use intptr_t for onTouch argument.

tools/viewer/Viewer.cpp

Index: tools/viewer/Viewer.cpp
diff --git a/tools/viewer/Viewer.cpp b/tools/viewer/Viewer.cpp
index 7e345c5bbc8032420f3200e563fa7208c123878d..c11b82bec0e997c1a11a77d864d9091e77db9fbc 100644
--- a/tools/viewer/Viewer.cpp
+++ b/tools/viewer/Viewer.cpp
@@ -28,7 +28,7 @@ static void on_paint_handler(SkCanvas* canvas, void* userData) {
     return vv->onPaint(canvas);
 }
 
-static bool on_touch_handler(int owner, Window::InputState state, float x, float y, void* userData)
+static bool on_touch_handler(intptr_t owner, Window::InputState state, float x, float y, void* userData)
 {
     Viewer* viewer = reinterpret_cast<Viewer*>(userData);
 
@@ -332,7 +332,7 @@ void Viewer::onPaint(SkCanvas* canvas) {
     fCommands.drawHelp(canvas);
 }
 
-bool Viewer::onTouch(int owner, Window::InputState state, float x, float y) {
+bool Viewer::onTouch(intptr_t owner, Window::InputState state, float x, float y) {
     void* castedOwner = reinterpret_cast<void*>(owner);
     SkPoint touchPoint = fDefaultMatrixInv.mapXY(x, y);
     switch (state) {