Do not instantiate Labels

until required. In the worst case if the regex is wrong is parses out
something that our Label implementation rejects it will appear in the
error list.

This change is to make it easier to understand why and what kind of
labels is instantiated during build operations.

Bug: n/a
Test: n/a
Change-Id: I53a6371be1ec2fc38dcd74acb7b2038e2612a064

AOSP: 3e7c8ecfb0ccdc4fbe9e1bdfa862f2b267e87b0a

base/src/com/google/idea/blaze/base/run/filter/BlazeTargetFilter.java

@@ -23,6 +23,7 @@
 import com.google.idea.blaze.base.settings.Blaze;
 import com.intellij.execution.filters.ConsoleFilterProvider;
 import com.intellij.execution.filters.Filter;
+import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.markup.EffectType;
 import com.intellij.openapi.editor.markup.TextAttributes;
 import com.intellij.openapi.project.Project;
@@ -63,13 +64,13 @@ public Result applyFilter(String line, int entireLength) {
       int prefixLength = Optional.ofNullable(matcher.group(1)).map(String::length).orElse(0);
 
       String labelString = matcher.group().substring(prefixLength);
-      Label label = LabelUtils.createLabelFromString(/* blazePackage= */ null, labelString);
-      if (label == null) {
-        continue;
-      }
       // for performance reasons, don't resolve until the user clicks the link
       NonProblemHyperlinkInfo link =
           project -> {
+            Label label = LabelUtils.createLabelFromString(/* blazePackage= */ null, labelString);
+            if (label == null) {
+              Logger.getInstance(this.getClass()).error(new IllegalStateException("Parsing returned illegal label: " + labelString));
+            }
             PsiElement psi = BuildReferenceManager.getInstance(project).resolveLabel(label);
             if (psi instanceof NavigatablePsiElement) {
               ((NavigatablePsiElement) psi).navigate(true);