Replace `fallible` boolean arguments with an enum

[jdm]

Various methods in WebGL objects have fallible arguments that are used to support operations that can fail during object destruction that do not indicate a total failure. We should replace these booleans with a enum Operation { Fallible, Infallible } instead to make the code readable:

Code:

• servo/components/script/dom/webgltexture.rs

  Line 192 in cf725fc

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglbuffer.rs

  Lines 94 to 104 in cf725fc

  	pub fn mark_for_deletion(&self, fallible: bool) {
  	if self.marked_for_deletion.get() {
  	return;
  	}
  	self.marked_for_deletion.set(true);
  	if self.is_deleted() {
  	self.delete(fallible);
  	}
  	}
  	fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglvertexarrayobject.rs

  Line 44 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglvertexarrayobjectoes.rs

  Line 44 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglsampler.rs

  Line 93 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglsync.rs

  Line 85 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webgltransformfeedback.rs

  Line 101 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglquery.rs

  Line 99 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglrenderbuffer.rs

  Line 93 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/vertexarrayobject.rs

  Line 47 in a927f1a

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglprogram.rs

  Line 87 in 67b4336

  pub fn mark_for_deletion(&self, fallible: bool) {

• servo/components/script/dom/webglshader.rs

  Line 306 in 67b4336

  pub fn mark_for_deletion(&self, fallible: bool) {

• servo/components/script/dom/webgltexture.rs

  Line 186 in 67b4336

  pub fn delete(&self, fallible: bool) {

• servo/components/script/dom/webglframebuffer.rs

  Line 205 in 67b4336

  pub fn delete(&self, fallible: bool) {

[highfive]

Hi! If you have any questions regarding this issue, feel free to make a comment here, or ask it in the #servo channel in IRC.

If you intend to work on this issue, then add @highfive: assign me to your comment, and I'll assign this to you. 😄

[skrzyp1]

@highfive: assign me
I'll try to do it as i seems beginner friendly.

[highfive]

Hey @skrzyp1! Thanks for your interest in working on this issue. It's now assigned to you!

[akshay1992kalbhor]

Where would the enum be defined? Its being used my multiple WebGL objects. Also do we need a new name for the second argument now that its an enum? Something like 'operation_fallibility' instead of 'fallible'?

[jdm]

Defining the enum in webglrenderingcontext.rs is probably fine; I think all of those files already import things from that module. Renaming it like you suggest sounds fine.

[skrzyp1]

Sorry i forgot about that ill get to work unless its already WiP by someone else

[akshay1992kalbhor]

I haven't started working on the issue yet. Just wanted to know how to solve it. I know it was assigned to you so if you still want to work on it go ahead! Sorry for the confusion.

[he4d]

@highfive: assign me
I will try this

[highfive]

Hey @he4d! Thanks for your interest in working on this issue. It's now assigned to you!

[he4d]

Do I need to write some tests for this?

[jdm]

No - if it builds, that's good enough for a PR.