Stale visualize_color_gamut.cpp reference in tools.gyp

TBR=msarett@google.com

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4775

Change-Id: I6ca3379ca9578dc9a7f158a1a01b6a73bf301f17
Reviewed-on: https://skia-review.googlesource.com/4775
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Matt Sarett <msarett@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>

gyp/tools.gyp

diff --git a/gyp/tools.gyp b/gyp/tools.gyp
index 2e1aaab..b4ce755 100644
--- a/gyp/tools.gyp
+++ b/gyp/tools.gyp
@@ -485,7 +485,7 @@
       'target_name': 'visualize_color_gamut',
       'type': 'executable',
       'sources': [
-        '../tools/visualize_color_gamut.cpp',
+        '../tools/colorspaceinfo.cpp',
       ],
       'include_dirs': [
         '../src/core',