[clangd] Enable SuggestMissingIncludes by default.

Summary: This seems to work stably now. Turn on by default.

Reviewers: kadircet

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58772

llvm-svn: 355200

clang-tools-extra/clangd/tool/ClangdMain.cpp

@@ -217,7 +217,7 @@ static llvm::cl::opt<bool> SuggestMissingIncludes(
     "suggest-missing-includes",
     llvm::cl::desc("Attempts to fix diagnostic errors caused by missing "
                    "includes using index."),
-    llvm::cl::init(false));
+    llvm::cl::init(true));
 
 namespace {