What steps will reproduce the problem?
Use a browser with a good rendering engine to go to
http://lindenbergsoftware.com/google/noto/bali-taling.html
The table on this page shows the different Balinese taling marks combined with 
different base characters. In each cell of the table, the first line uses Noto 
Sans Balinese, the second line the Aksara Bali font.

What is the expected output?
The taling or taling repa component of each cluster should be shown on the left 
side of the base character, the way the Aksara Bali font does. See also the 
Unicode reference glyphs at
http://www.unicode.org/charts/PDF/U1B00.pdf

What do you see instead?
The taling or taling repa component is shown on the right side of the base in 
the following cases:
– By Firefox in all combinations that include the tedung component in a 
precomposed form, i.e., the U+1B40 and U+1B41 code points.
– By Safari in all combinations.
See the attached screen shots.

What version of the product are you using? On what operating system?
Noto Sans Balinese Regular 1.02
Mozilla Firefox Nightly 35.0a1 (2014-09-25) on Mac OS X 10.9.5.
Safari on iOS 8.0.2.

Please provide any additional information below.
According to the Mozilla commit log, Firefox has recently been updated to 
Harfbuzz 0.9.34. Firefox is clearly not using OS X rendering, as other 
applications on OS X 10.9.5 render Noto Sans Balinese quite differently.