Add option to compile out DCHECKs in android webview

To support performance testing since DCHECKs can have a measurable
impact on performance.

BUG=
NOTRY=true

Review URL: https://codereview.chromium.org/118803004

git-svn-id: http://src.chromium.org/svn/trunk/src/build@242778 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/envsetup_functions.sh

@@ -311,6 +311,10 @@ ${ANDROID_SDK_VERSION}
     DEFINES+=" android_full_debug=1"
     DEFINES+=" android_use_tcmalloc=1"
   fi
+  if [[ -n "$CHROME_ANDROID_WEBVIEW_OFFICIAL_BUILD" ]]; then
+    DEFINES+=" logging_like_official_build=1"
+    DEFINES+=" tracing_like_official_build=1"
+  fi
   export GYP_DEFINES="${DEFINES}"
 
   export GYP_GENERATORS="android"