ignore ctx.restore() if in the initial state

calling cairo_restore on the initial state makes all drawing operations
afterwards do nothing, which does not match browser behavior

also merges save+saveState, restore+restoreState functions

src/CanvasRenderingContext2d.cc

@@ -191,8 +191,13 @@ Context2d::~Context2d() {
 
 void
 Context2d::save() {
- cairo_save(_context);
- saveState();
+ if (stateno < CANVAS_MAX_STATES) {
+ cairo_save(_context);
+ states[++stateno] = (canvas_state_t *) malloc(sizeof(canvas_state_t));
+ memcpy(states[stateno], state, sizeof(canvas_state_t));
+ states[stateno]->fontDescription = pango_font_description_copy(states[stateno-1]->fontDescription);
+ state = states[stateno];
+ }
 }
 
 /*
@@ -201,35 +206,14 @@ Context2d::save() {
 
 void
 Context2d::restore() {
- cairo_restore(_context);
- restoreState();
-}
-
-/*
- * Save the current state.
- */
-
-void
-Context2d::saveState() {
- if (stateno == CANVAS_MAX_STATES) return;
- states[++stateno] = (canvas_state_t *) malloc(sizeof(canvas_state_t));
- memcpy(states[stateno], state, sizeof(canvas_state_t));
- states[stateno]->fontDescription = pango_font_description_copy(states[stateno-1]->fontDescription);
- state = states[stateno];
-}
-
-/*
- * Restore state.
- */
-
-void
-Context2d::restoreState() {
- if (0 == stateno) return;
- pango_font_description_free(states[stateno]->fontDescription);
- free(states[stateno]);
- states[stateno] = NULL;
- state = states[--stateno];
- pango_layout_set_font_description(_layout, state->fontDescription);
+ if (stateno > 0) {
+ cairo_restore(_context);
+ pango_font_description_free(states[stateno]->fontDescription);
+ free(states[stateno]);
+ states[stateno] = NULL;
+ state = states[--stateno];
+ pango_layout_set_font_description(_layout, state->fontDescription);
+ }
 }
 
 /*