Use float (not int) for OpenGL shader.
Use float (not int) for OpenGL shader.

There was multiplication between an int and a float that caused Android
builds to fail. We should only use floats (e.g., float a = 1.0 * b;
instead of float a = 1 * b;)

Bug: Issue 27793529

Tested:
Works on Linux, Nexus 5X.

Change-Id: Idea75bb0fe93e54e77760fa9cfabea7d27b676ef

google/zooshi,google/zooshi,google/zooshi,google/zooshi,google/zooshi