API: computed: Change css_computed_width getter function names

Now `css_computed_width()` is unchanged from how it always was.
And `css_computed_width_px()` is the new function to convert to
device pixels.

Also improve `css_computed_width_px()` API documentation.

include/libcss/computed.h

@@ -280,23 +280,28 @@ uint8_t css_computed_max_width(
 		css_fixed *length, css_unit *unit);
 
 /**
+ * Get the width property value in device pixels.
+ *
+ * \note  If available_px is set to a negative number (invalid) then,
+ *        if the computation would have required a valid available
+ *        width, it will return CSS_WIDTH_AUTO.
+ *
+ * This will resolve `calc()` expressions to used values.
+ *
  * \param[in]  style         A computed style.
  * \param[in]  unit_ctx      Unit conversion context.
  * \param[in]  available_px  The available width in pixels.
- *                           If set to a negative number (invalid) then if the
- *                           computation would have required a valid available
- *                           width, then it will return CSS_WIDTH_AUTO.
  * \param[out] px_out        Returns width in pixels if and only if the
  *                           call returns CSS_WIDTH_SET.
  * \return CSS_WIDTH_SET or CSS_WIDTH_AUTO.
  */
-uint8_t css_computed_width(
+uint8_t css_computed_width_px(
 		const css_computed_style *style,
 		const css_unit_ctx *unit_ctx,
 		int available_px,
 		int *px_out);
 
-uint8_t css_computed_width_static(const css_computed_style *style,
+uint8_t css_computed_width(const css_computed_style *style,
 		css_fixed *length, css_unit *unit);
 
 uint8_t css_computed_empty_cells(

src/select/computed.c

@@ -702,7 +702,7 @@ uint8_t css_computed_max_width(const css_computed_style *style,
 	return get_max_width(style, length, unit);
 }
 
-uint8_t css_computed_width(
+uint8_t css_computed_width_px(
 		const css_computed_style *style,
 		const css_unit_ctx *unit_ctx,
 		int available_px,
@@ -753,7 +753,7 @@ uint8_t css_computed_width(
 	return type;
 }
 
-uint8_t css_computed_width_static(const css_computed_style *style,
+uint8_t css_computed_width(const css_computed_style *style,
 		css_fixed *length, css_unit *unit)
 {
 	css_fixed_or_calc length_ = {.value = 0};

test/dump_computed.h

@@ -3147,9 +3147,9 @@ static void dump_computed_style(const css_computed_style *style, char *buf,
 
 	/* width */
 #ifdef USE_DEVICE
-	val = css_computed_width(style, unit_ctx, 1024, &pixels);
+	val = css_computed_width_px(style, unit_ctx, 1024, &pixels);
 #else
-	val = css_computed_width_static(style, &len1, &unit1);
+	val = css_computed_width(style, &len1, &unit1);
 #endif
 	switch (val) {
 	case CSS_WIDTH_INHERIT: