Implement C path functions

Mainly just to familiarize myself with this code.

Review URL: https://codereview.chromium.org/633183002

experimental/sk_surface.cpp

@@ -27,6 +27,10 @@ static const SkPath& AsPath(const sk_path_t& cpath) {
     return reinterpret_cast<const SkPath&>(cpath);
 }
 
+static SkPath* as_path(sk_path_t* cpath) {
+    return reinterpret_cast<SkPath*>(cpath);
+}
+
 static const SkImage* AsImage(const sk_image_t* cimage) {
     return reinterpret_cast<const SkImage*>(cimage);
 }
@@ -102,6 +106,32 @@ void sk_paint_set_color(sk_paint_t* cpaint, sk_color_t c) {
 
 ///////////////////////////////////////////////////////////////////////////////////////////
 
+sk_path_t* sk_path_new() {
+    return (sk_path_t*)SkNEW(SkPath);
+}
+
+void sk_path_delete(sk_path_t* cpath) {
+    SkDELETE(as_path(cpath));
+}
+
+void sk_path_move_to(sk_path_t* cpath, float x, float y) {
+    as_path(cpath)->moveTo(x, y);
+}
+
+void sk_path_line_to(sk_path_t* cpath, float x, float y) {
+    as_path(cpath)->lineTo(x, y);
+}
+
+void sk_path_quad_to(sk_path_t* cpath, float x0, float y0, float x1, float y1) {
+    as_path(cpath)->quadTo(x0, y0, x1, y1);
+}
+
+void sk_path_close(sk_path_t* cpath) {
+    as_path(cpath)->close();
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////
+
 void sk_canvas_save(sk_canvas_t* ccanvas) {
     AsCanvas(ccanvas)->save();
 }
@@ -196,11 +226,20 @@ void sk_test_capi(SkCanvas* canvas) {
     sk_paint_set_color(cpaint, 0xFF00FF00);
     sk_canvas_draw_rect(ccanvas, &cr, cpaint);
     
+    sk_path_t* cpath = sk_path_new();
+    sk_path_move_to(cpath, 50, 50);
+    sk_path_line_to(cpath, 100, 100);
+    sk_path_line_to(cpath, 50, 100);
+    sk_path_close(cpath);
+
+    sk_canvas_draw_path(ccanvas, cpath, cpaint);
+
     sk_image_t* cimage = sk_surface_new_image_snapshot(csurface);
     
     // HERE WE CROSS THE C..C++ boundary
     canvas->drawImage((const SkImage*)cimage, 20, 20, NULL);
     
+    sk_path_delete(cpath);
     sk_paint_delete(cpaint);
     sk_image_unref(cimage);
     sk_surface_delete(csurface);

experimental/sk_surface.h

@@ -52,16 +52,17 @@ typedef struct {
 typedef struct sk_path_t sk_path_t;
 
 sk_path_t* sk_path_new();
+void sk_path_delete(sk_path_t*);
 void sk_path_move_to(sk_path_t*, float x, float y);
 void sk_path_line_to(sk_path_t*, float x, float y);
 void sk_path_quad_to(sk_path_t*, float x0, float y0, float x1, float y1);
-void sk_path_get_bounds(const sk_path_t*, sk_rect_t*);
+void sk_path_close(sk_path_t*);
 
 typedef struct sk_paint_t sk_paint_t;
 
 sk_paint_t* sk_paint_new();
 void sk_paint_delete(sk_paint_t*);
-bool sk_paint_is_antialias(sk_paint_t*);
+bool sk_paint_is_antialias(const sk_paint_t*);
 void sk_paint_set_antialias(sk_paint_t*, bool);
 sk_color_t sk_paint_get_color(const sk_paint_t*);
 void sk_paint_set_color(sk_paint_t*, sk_color_t);

gyp/experimental.gyp

@@ -12,6 +12,8 @@
         '../experimental/SkSetPoly3To3.cpp',
         '../experimental/SkSetPoly3To3_A.cpp',
         '../experimental/SkSetPoly3To3_D.cpp',
+        '../experimental/sk_surface.h',
+        '../experimental/sk_surface.cpp',
       ],
       'direct_dependent_settings': {
         'include_dirs': [