Enable --use_top_level_targets_for_symlinks by default.

RELNOTES: Enable --use_top_level_targets_for_symlinks by default.
PiperOrigin-RevId: 454603210
Change-Id: I9bb2f0a46beeff27798b2a6006d5763ae5ff75c7

Author: Googler

src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java

@@ -344,7 +344,7 @@ public String getSymlinkPrefix(String productName) {
   // To be made a no-op and deleted once new symlink behavior is battle-tested.
   @Option(
       name = "use_top_level_targets_for_symlinks",
-      defaultValue = "false",
+      defaultValue = "true",
       documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
       effectTags = {OptionEffectTag.AFFECTS_OUTPUTS},
       help =

src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java

@@ -726,6 +726,7 @@ private ImmutableList<ConvenienceSymlink> createConvenienceSymlinks(
     // Gather configurations to consider.
     Set<BuildConfigurationValue> targetConfigurations =
         buildRequestOptions.useTopLevelTargetsForSymlinks()
+                && !analysisResult.getTargetsToBuild().isEmpty()
             ? analysisResult.getTargetsToBuild().stream()
                 .map(ConfiguredTarget::getActual)
                 .map(ConfiguredTarget::getConfigurationKey)