ANSI color codes are not interpreted in build output

Steps to Reproduce

1. Create source that would trigger a compiler error. For example main.c:

   #include <stdio.h>
   void main(void)
   {
     printf("Hello world!")
   }
   

2. Use a compiler that produces colourized output in a build script (for example use the wrapper colorgcc for gcc)

   colorgcc -o hello main.c
   

3. Run a build
4. Open the build log
5. Click on the View link

Expected Results

If ANSI colour codes are present then the ANSI colour codes are interpreted and the text is coloured

Actual Results

The build log is displayed as raw data.

From BAM-20384

It would be nice to support full RGB palette. It may help to read complex execution logs.
ANSI color support was implemented in BAM-10855.

Convertion details described in hterm terminal documentation:
https://chromium.googlesource.com/apps/libapps/+/HEAD/hterm/doc/ControlSequences.md#SGR-extended-color