[release.0.4] all: merge master into gopls-release-branch.0.4

Change-Id: I5dac68f22ca1cf574238b0b217658abf7cccf5f8
diff --git a/internal/lsp/debug/info.go b/internal/lsp/debug/info.go
index b070c99..3531353 100644
--- a/internal/lsp/debug/info.go
+++ b/internal/lsp/debug/info.go
@@ -23,7 +23,7 @@
 )
 
 // Version is a manually-updated mechanism for tracking versions.
-var Version = "master"
+var Version = "0.4.2"
 
 // PrintServerInfo writes HTML debug info to w for the Instance.
 func (i *Instance) PrintServerInfo(ctx context.Context, w io.Writer) {
diff --git a/internal/lsp/source/options.go b/internal/lsp/source/options.go
index 92c09e8..daf4b4b 100644
--- a/internal/lsp/source/options.go
+++ b/internal/lsp/source/options.go
@@ -608,7 +608,7 @@
 			Analyzer:       fillreturns.Analyzer,
 			enabled:        true,
 			FixesError:     fillreturns.FixesError,
-			HighConfidence: true,
+			HighConfidence: false,
 		},
 		nonewvars.Analyzer.Name: {
 			Analyzer:   nonewvars.Analyzer,