chore(travis): report bad code excerpts (BAD FILENAME) in docs (#2154)

* chore(travis): report bad code excerpts (BAD FILENAME)

* Only ignore build dir under dart dir

Have the shredder ignore `**/dart/build/**`.

scripts/check-docs.sh

@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+
+set -e -o pipefail
+
+[[ -z "$NGIO_ENV_DEFS" ]] && . ./scripts/env-set.sh > /dev/null
+if [[ "x$1" == "x-v" ]]; then VERBOSE=1; shift; fi
+
+SITE=./www
+
+CHECK_FOR=bad-code-excerpt
+
+LOGFILE_PREFIX=$CHECK_FOR-log
+LOGFILE_FULL=$TMP/$LOGFILE_PREFIX-full.txt
+LOGFILE=$TMP/$LOGFILE_PREFIX.txt
+
+SKIPFILE_BASE=$CHECK_FOR-skip-patterns.txt
+SKIPFILE_SRC=./scripts/config/$SKIPFILE_BASE
+SKIPFILE=$TMP/$SKIPFILE_BASE
+
+if [[ ! -d $SITE ]]; then
+    echo "Missing site folder $SITE"
+    exit 1;
+fi
+
+travis_fold start $CHECK_FOR
+echo "Searching site for HTML files containing bad code excerpts (BAD FILENAME)."
+echo
+
+if [[ -n "$VERBOSE" ]]; then
+    travis_fold start $CHECK_FOR-details
+    echo "Full file list with grep details:"
+    find $SITE -type f -name "*.html" -exec grep -Hne "BAD FILENAME" {} \; | tee $LOGFILE_FULL
+    travis_fold end $CHECK_FOR-details
+    echo
+else
+    echo "Full file list:"
+    find $SITE -type f -name "*.html" -exec grep -le "BAD FILENAME" {} \; | tee $LOGFILE_FULL
+fi
+
+echo
+echo "Skip patterns for paths of files known to have issues ($SKIPFILE_SRC):"
+
+perl -pe 's/(\s+|\s*#.*)$/\n/g' $SKIPFILE_SRC | \
+    # Remove blank lines \
+    grep '.' > $SKIPFILE
+cat $SKIPFILE
+echo
+echo "File list excluding those matching skip patterns:"
+grep -v -E -f $SKIPFILE $LOGFILE_FULL | tee $LOGFILE || true
+
+if [[ ! -s $LOGFILE ]]; then
+    echo "No matches, all is good!"
+    travis_fold end $CHECK_FOR
+else
+    exit 1;
+fi

scripts/config/bad-code-excerpt-skip-patterns.txt

@@ -0,0 +1,6 @@
+# Comments & blank lines are ignored. Entry format (make pattern as specific as possible):
+# <grep-pattern-to-match-file-path> # reason / issue number
+
+/[jt]s/.*/api/router-deprecated/    # Obsolete API entries. No issue open yet.
+/ts/latest/guide/style-guide.html   # https://github.com/angular/angular.io/issues/2123
+/ts/latest/guide/upgrade.html       # In a transient state until RC6 - @filipe.silva