Export of internal Abseil changes.

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586c41e29e80d9613434f18347d4a70a92a90989 by Jon Cohen <cohenjon@google.com>:

Whitespace cleanup

PiperOrigin-RevId: 207119388

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e28fc6932d68f7097918f3092079f07112e684c1 by Abseil Team <absl-team@google.com>:

Fix comment typo in mutex.h

PiperOrigin-RevId: 207024211

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b7714a5f189b2863f9cfc285ba428ca2059b83f4 by Abseil Team <absl-team@google.com>:

Raise the floor for gcc from gcc 4.7 to gcc 4.8.

PiperOrigin-RevId: 207021220

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262ae79150278ea1b4e512dfe8ff05c32768f429 by Matt Armstrong <marmstrong@google.com>:

Raise the floor for gcc from gcc 4.7 to gcc 4.8.

PiperOrigin-RevId: 206997741

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5aba0b15eaf6c5beff0e91670a7cdf5ad1151886 by Derek Mauro <dmauro@google.com>:

Use std::chrono to get the current time on both Apple and Windows
platforms, eliminating the unnecessarily complicated logic on Apple
platforms.

PiperOrigin-RevId: 206979219

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807a91adf876f7532050d442f00268754c0f260b by Derek Mauro <dmauro@google.com>:

Fix multiple definition problem when Abseil is combined with
gperftools on PowerPC.

https://github.com/abseil/abseil-cpp/pull/152

PiperOrigin-RevId: 206963083
GitOrigin-RevId: 586c41e29e80d9613434f18347d4a70a92a90989
Change-Id: I0ee65a733c423890b97dd3500f2d17449792387c

1 files changed, 29 insertions, 0 deletions

diff --git a/absl/time/internal/get_current_time_chrono.inc b/absl/time/internal/get_current_time_chrono.inc
new file mode 100644
index 0000000..cf884a1
--- /dev/null
+++ b/absl/time/internal/get_current_time_chrono.inc
@@ -0,0 +1,29 @@
+// Copyright 2018 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <chrono>
+#include <cstdint>
+
+namespace absl {
+namespace time_internal {
+
+static int64_t GetCurrentTimeNanosFromSystem() {
+  return std::chrono::duration_cast<std::chrono::nanoseconds>(
+             std::chrono::system_clock::now() -
+             std::chrono::system_clock::from_time_t(0))
+      .count();
+}
+
+}  // namespace time_internal
+}  // namespace absl