clang-tidy - silence static analyzer getAs<> null dereference warnings. NFCI.

The static analyzer is warning about potential null dereferences, but in these cases we should be able to use castAs<> directly and if not assert will fire for us.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@375102 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/clang-tidy/misc/RedundantExpressionCheck.cpp b/clang-tidy/misc/RedundantExpressionCheck.cpp
index 3cec1fb..e646ee9 100644
--- a/clang-tidy/misc/RedundantExpressionCheck.cpp
+++ b/clang-tidy/misc/RedundantExpressionCheck.cpp
@@ -478,7 +478,7 @@
   // These functions must be declared const in order to not be able to modify
   // the instance of the class they are called through.
   if (ParamCount == 1 &&
-      !OperatorDecl->getType()->getAs<FunctionType>()->isConst())
+      !OperatorDecl->getType()->castAs<FunctionType>()->isConst())
     return true;
 
   if (isNonConstReferenceType(OperatorDecl->getParamDecl(0)->getType()))
diff --git a/clang-tidy/modernize/UseDefaultMemberInitCheck.cpp b/clang-tidy/modernize/UseDefaultMemberInitCheck.cpp
index 3c2e0e9..1e59acb 100644
--- a/clang-tidy/modernize/UseDefaultMemberInitCheck.cpp
+++ b/clang-tidy/modernize/UseDefaultMemberInitCheck.cpp
@@ -29,7 +29,7 @@
     return "false";
 
   case Type::STK_Integral:
-    switch (InitType->getAs<BuiltinType>()->getKind()) {
+    switch (InitType->castAs<BuiltinType>()->getKind()) {
     case BuiltinType::Char_U:
     case BuiltinType::UChar:
     case BuiltinType::Char_S:
@@ -47,7 +47,7 @@
     }
 
   case Type::STK_Floating:
-    switch (InitType->getAs<BuiltinType>()->getKind()) {
+    switch (InitType->castAs<BuiltinType>()->getKind()) {
     case BuiltinType::Half:
     case BuiltinType::Float:
       return "0.0f";
@@ -58,10 +58,10 @@
   case Type::STK_FloatingComplex:
   case Type::STK_IntegralComplex:
     return getValueOfValueInit(
-        InitType->getAs<ComplexType>()->getElementType());
+        InitType->castAs<ComplexType>()->getElementType());
 
   case Type::STK_FixedPoint:
-    switch (InitType->getAs<BuiltinType>()->getKind()) {
+    switch (InitType->castAs<BuiltinType>()->getKind()) {
     case BuiltinType::ShortAccum:
     case BuiltinType::SatShortAccum:
       return "0.0hk";