base: use COMPILER_MSVC macro instead of checking _MSC_VER

And mark CPU class as final.

BUG=None

Change-Id: Iaf9f96f388bbeca689114cd4c935c354ba8c8b3f
Reviewed-on: https://chromium-review.googlesource.com/538638
Commit-Queue: Thiago Farina <tfarina@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#480266}

base/cpu.cc

@@ -19,7 +19,7 @@
 #endif
 
 #if defined(ARCH_CPU_X86_FAMILY)
-#if defined(_MSC_VER)
+#if defined(COMPILER_MSVC)
 #include <intrin.h>
 #include <immintrin.h>  // For _xgetbv()
 #endif
@@ -54,7 +54,7 @@ CPU::CPU()
 namespace {
 
 #if defined(ARCH_CPU_X86_FAMILY)
-#ifndef _MSC_VER
+#if !defined(COMPILER_MSVC)
 
 #if defined(__pic__) && defined(__i386__)
 
@@ -89,7 +89,7 @@ uint64_t _xgetbv(uint32_t xcr) {
   return (static_cast<uint64_t>(edx) << 32) | eax;
 }
 
-#endif  // !_MSC_VER
+#endif  // !defined(COMPILER_MSVC)
 #endif  // ARCH_CPU_X86_FAMILY
 
 #if defined(ARCH_CPU_ARM_FAMILY) && (defined(OS_ANDROID) || defined(OS_LINUX))

base/cpu.h

@@ -12,9 +12,8 @@
 namespace base {
 
 // Query information about the processor.
-class BASE_EXPORT CPU {
+class BASE_EXPORT CPU final {
  public:
-  // Constructor
   CPU();
 
   enum IntelMicroArchitecture {

base/process/memory_unittest.cc

@@ -38,7 +38,7 @@
 
 #if defined(OS_WIN)
 
-#if defined(_MSC_VER)
+#if defined(COMPILER_MSVC)
 // ssize_t needed for OutOfMemoryTest.
 #if defined(_WIN64)
 typedef __int64 ssize_t;

base/strings/safe_sprintf.h

@@ -21,7 +21,7 @@
 namespace base {
 namespace strings {
 
-#if defined(_MSC_VER)
+#if defined(COMPILER_MSVC)
 // Define ssize_t inside of our namespace.
 #if defined(_WIN64)
 typedef __int64 ssize_t;