Do not filter using analyze step if layout tests are modified.

testing/buildbot/trybot_analyze_config.json

 {
   "android_webview": {
     "exclusions": [
       "android_webview/.*"
     ]
   },
   "base": {
     "exclusions": [
       ".*isolate",
       "build/.*gyp[i]?",
       "build/android/.*py",
       "build/android/devil/.*",
       "build/android/play_services/.*",
       "build/android/pylib/.*",
       "build/compiler_version.py",
       "build/get_landmines.py",
       "build/gyp_chromium",
       "build/linux/sysroot_ld_path.sh",
       "build/toolchain/get_concurrent_links.py",
       "build/toolchain/mac/.*py",
       "build/util/lib/common/unittest_util.py",
       "infra/.*",
       "DEPS",
       "testing/buildbot/.*",
       "testing/scripts/.*",
       "testing/test_env.py",
       "third_party/android_platform/development/scripts/.*",
+      "third_party/WebKit/LayoutTests/.*",

[qyearsley, 2016/07/28 23:33:29]

Maybe this should be "third_party/WebKit/.*" -- then the analyze step would be
ignored for all CLs that modify anything in Blink, I believe?

As far as I understand, the purpose of the "analyze" step is to pare down the
list of targets to build (and tests to run) to avoid wasting resources -- so if
this exclusion list is too broad, then the negative effect would be potentially
running some unnecessary tests, but it would never fail to run a test should be
run, right?

[Dirk Pranke, 2016/07/29 23:58:55]

In GN, you can actually set a "data" attribute on a build target, and if
something listed in that target changes, then the target will be considered
affected.

I.e., instead of doing this, you should add `data = [
"//third_party/WebKit/LayoutTests/", "//third_party/WebKit/Tools/Scripts/"]` to
the blink_tests target in //BUILD.gn

       "tools/clang/blink_gc_plugin/CMakeLists.txt",
       "tools/luci-go/.*"
     ]
   },
   "chromium": {
     "exclusions": [
       "chrome/browser/resources/.*(css|html|js)",
       "chrome/browser/ui/webui/.*browsertest.*js",
       "chrome/installer/linux/sysroot_scripts/install-debian.wheezy.sysroot.py",
       "chrome/test/data/.*",
@@ skipping 25 matching lines @@
       "tools/telemetry/.*",
       "ui/webui/resources/.*(css|html|js)"
     ]
   },
   "ios": {
     "exclusions": [
       "ios/build/bots/.*"
     ]
   }
 }