Warnings about lint baseline files working as intended are not useful.
Added a gradle property checkLintBaseline that re-enables those
warnings.
This is part of an ongoing effort to make gradle output more useful.

Test: ./gradlew lint ; ./gradlew lint -PcheckLintBaseline
Result: output length reduced 60%, no valuable information lost

However, more work remains to be done on suppressing non-useful lint
baseline warnings.

Change-Id: Ib7ed690f2d0880e687ff5356203ab525f599eb0b
diff --git a/buildSrc/lint.xml b/buildSrc/lint.xml
new file mode 100644
index 0000000..e780a7a
--- /dev/null
+++ b/buildSrc/lint.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<lint>
+    <issue id="LintBaseline" severity="ignore">
+        <ignore regexp=".* filtered out because .* listed in the baseline file.*"/>
+    </issue>
+</lint>
\ No newline at end of file