[Clang] Remove unused-using declarations.

[hokein]

Summary

These are found by mis-unused-using-decls check.

lib/StaticAnalyzer/Checkers/MallocOverflowSecurityChecker.cpp

 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
 #include "clang/StaticAnalyzer/Core/Checker.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
 #include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/SmallVector.h"
 
 using namespace clang;
 using namespace ento;
-using llvm::APInt;
 using llvm::APSInt;
 
 namespace {
 struct MallocOverflowCheck {
   const BinaryOperator *mulop;
   const Expr *variable;
   APSInt maxVal;
 

lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp

 #include "llvm/Support/Program.h"
 #include "llvm/Support/Timer.h"
 #include "llvm/Support/raw_ostream.h"
 #include <memory>
 #include <queue>
 
 using namespace clang;
 using namespace ento;
-using llvm::SmallPtrSet;
 
 #define DEBUG_TYPE "AnalysisConsumer"
 
 static std::unique_ptr<ExplodedNode::Auditor> CreateUbiViz();
 
 STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
 STATISTIC(NumFunctionsAnalyzed,
                       "The # of functions and blocks analyzed (as top level "

unittests/AST/ASTContextParentMapTest.cpp

 #include "clang/ASTMatchers/ASTMatchers.h"
 #include "clang/Tooling/Tooling.h"
 #include "gtest/gtest.h"
 
 namespace clang {
 namespace ast_matchers {
 
 using clang::tooling::newFrontendActionFactory;
-using clang::tooling::runToolOnCodeWithArgs;
-using clang::tooling::FrontendActionFactory;
 
 TEST(GetParents, ReturnsParentForDecl) {
   MatchVerifier<Decl> Verifier;
   EXPECT_TRUE(
       Verifier.match("class C { void f(); };",
                      cxxMethodDecl(hasParent(recordDecl(hasName("C"))))));
 }
 

unittests/AST/ASTImporterTest.cpp

 #include "clang/ASTMatchers/ASTMatchers.h"
 #include "clang/Tooling/Tooling.h"
 #include "gtest/gtest.h"
 
 namespace clang {
 namespace ast_matchers {
 
 using clang::tooling::newFrontendActionFactory;
-using clang::tooling::runToolOnCodeWithArgs;
-using clang::tooling::FrontendActionFactory;
 
 typedef std::vector<std::string> StringVector;
 
 void getLangArgs(Language Lang, StringVector &Args) {
   switch (Lang) {
   case Lang_C:
     Args.insert(Args.end(), { "-x", "c", "-std=c99" });
     break;

unittests/ASTMatchers/Dynamic/VariantValueTest.cpp

 #include "clang/ASTMatchers/Dynamic/VariantValue.h"
 #include "gtest/gtest.h"
 
 namespace clang {
 namespace ast_matchers {
 namespace dynamic {
 namespace {
 
-using ast_matchers::internal::DynTypedMatcher;
-using ast_matchers::internal::Matcher;
-
 TEST(VariantValueTest, Unsigned) {
   const unsigned kUnsigned = 17;
   VariantValue Value = kUnsigned;
 
   EXPECT_TRUE(Value.isUnsigned());
   EXPECT_EQ(kUnsigned, Value.getUnsigned());
 
   EXPECT_TRUE(Value.hasValue());