Export of internal Abseil changes.

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714347c156cfe01575c1830a92bc6dea3030065b by Emma Christie <emmachristie@google.com>:

Release absl::EqualsIgnoreCase

PiperOrigin-RevId: 216243900

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688106e2b9d2924799d597682690851cfba87818 by Abseil Team <absl-team@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 216208373

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53638e4da238b230af0e56dc31b9fb790e708f36 by Emma Christie <emmachristie@google.com>:

Update StartsWithIgnoreCase(), EndsWithIgnoreCase(), and EqualsIgnoreCase() headers to say that these functions only consider ASCII case inputs.

PiperOrigin-RevId: 215930962
GitOrigin-RevId: 714347c156cfe01575c1830a92bc6dea3030065b
Change-Id: I7fb3506234185b1a961e0110c1f8302ffe7228fa

absl/time/internal/cctz/include/cctz/civil_time_detail.h

@@ -416,6 +416,12 @@ class civil_time {
     return difference(T{}, lhs.f_, rhs.f_);
   }
 
+  template <typename H>
+  friend H AbslHashValue(H h, civil_time a) {
+    return H::combine(std::move(h), a.f_.y, a.f_.m, a.f_.d,
+                                    a.f_.hh, a.f_.mm, a.f_.ss);
+  }
+
  private:
   // All instantiations of this template are allowed to call the following
   // private constructor and access the private fields member.

absl/time/internal/cctz/include/cctz/time_zone.h

@@ -224,6 +224,11 @@ class time_zone {
     return !(lhs == rhs);
   }
 
+  template <typename H>
+  friend H AbslHashValue(H h, time_zone tz) {
+    return H::combine(std::move(h), &tz.effective_impl());
+  }
+
   class Impl;
 
  private: