Added flag to enable WebGL 2.0 to about:flags

Still keeping the underlying flag as --enable-unsafe-es3-apis for the time being

BUG=295792

Review URL: https://codereview.chromium.org/1571913002

Cr-Commit-Position: refs/heads/master@{#368960}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index bf030ad..f8a7f14 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -2111,6 +2111,11 @@
      IDS_FLAGS_AUTOMATIC_TAB_DISCARDING_DESCRIPTION, kOsWin | kOsMac,
      FEATURE_VALUE_TYPE(features::kAutomaticTabDiscarding)},
 #endif  // OS_WIN || OS_MACOSX
+    {"enable-unsafe-es3-apis",
+     IDS_FLAGS_WEBGL2_NAME,
+     IDS_FLAGS_WEBGL2_DESCRIPTION,
+     kOsAll,
+     SINGLE_VALUE_TYPE(switches::kEnableUnsafeES3APIs)},
     // NOTE: Adding new command-line switches requires adding corresponding
     // entries to enum "LoginCustomFlags" in histograms.xml. See note in
     // histograms.xml and don't forget to run AboutFlagsHistogramTest unit test.