Match History Player Builds Bug

[CLIENT] Match History Player Builds Javascript Error

This is a bug for the online Match History page, specifically the Player Builds tab where the Item Purchase Order, Ability Order, Runes, and Masteries section fail to update doing specific steps. I'll be referring to the sections as A, B, C, and D in respect to the previous order stated from here out. (The best I could find, this bug seems to fit in the Client category for the Report a Bug board. If this is not the case, please update the "How to Report a Game Bug!" or "Welcome to Help and Support! Now, how do I get some help with my issue?" pinned discussions to reflect the correct location.)

Here is a match history that demonstrates this bug currently. I will be using it for the reproduction steps below this.

1. Select "Player Builds" tab (should be already selected in this case) a. Sections A, B, C, and D are loaded.
2. Select participant 5 (Soraka) a. Sections A, C, and D are loaded. Section B is not loaded.
3. Select a different participant (It does not seem to matter which champion is selected during this step, but I'll specifically choose participant 1, Master Yi, for direct steps) a. Sections C, and D are still loaded from previous participant. Section B is still not loaded. Section A is not loaded now as well.
4. Select a different participant besides participant 5 (Soraka) (It does not seem to matter which champion is selected during this step, but I'll specifically choose participant 2, Nasus) a. Sections A, B, C, and D are loaded correctly for the selected participant.
5. The bug seems to have remedied itself from here on until selecting participant 5 again. a. Section A is loaded. Sections B, C, and D are not loaded.
6. Select a different participant (It does not seem to matter which champion is selected during this step, but I'll specifically choose participant 3, Kog'Maw) a. Entire block containing A - D is no longer loaded.
7. From here on, steps 5-6 seem to repeat.

Browser: Chrome Version 42.0.2311.90 m (Latest) No extensions enabled.

From my minor investigation, it seems that this bug is caused by javascript not having a fallback for when a participant does not select a skill to level up during the match, as the error happens on a supposed array variable that assumes that it has a value at index 0. I, unfortunately, could not give a line number or the raw code because the code is obfuscated and minified without a source map directly available to the public.

> getSkill:function(){var d=this,a=d.skills[0].get("source"),c=a.getGame(),b=c.get("version");return DragonRamen.get("champion",b,a.get("champion")).getSkills().at(d.slot-1)}