style(src/Angular.js): make comment formatting consistent

Corrected formatting errors on lines 258, 695, 696, 1096, 1219, 1451, and 1536
by adding periods at the end of single line comments that were missing them
in order to be consistent with the formatting found in the file.

Capitalized the first letter in the first word of the comments on lines 695, 696, 1096,
to be consistent with the formatting of the rest of the file.

Added a space after the // in the comment on line 1536 to be
consistent with the formatting of the file.

Closes #11832