diff -r 000000000000 -r 6474c204b198 toolkit/crashreporter/google-breakpad/src/common/android/breakpad_getcontext_unittest.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/crashreporter/google-breakpad/src/common/android/breakpad_getcontext_unittest.cc	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,81 @@
+// Copyright (c) 2012, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <sys/ucontext.h>
+
+#include "breakpad_googletest_includes.h"
+#include "common/android/ucontext_constants.h"
+
+TEST(AndroidUContext, GRegsOffset) {
+#ifdef __arm__
+  // There is no gregs[] array on ARM, so compare to the offset of
+  // first register fields, since they're stored in order.
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.arm_r0));
+#elif defined(__i386__)
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.gregs));
+#define CHECK_REG(x) \
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_##x##_OFFSET),         \
+            offsetof(ucontext_t,uc_mcontext.gregs[REG_##x]))
+  CHECK_REG(GS);
+  CHECK_REG(FS);
+  CHECK_REG(ES);
+  CHECK_REG(DS);
+  CHECK_REG(EDI);
+  CHECK_REG(ESI);
+  CHECK_REG(EBP);
+  CHECK_REG(ESP);
+  CHECK_REG(EBX);
+  CHECK_REG(EDX);
+  CHECK_REG(ECX);
+  CHECK_REG(EAX);
+  CHECK_REG(TRAPNO);
+  CHECK_REG(ERR);
+  CHECK_REG(EIP);
+  CHECK_REG(CS);
+  CHECK_REG(EFL);
+  CHECK_REG(UESP);
+  CHECK_REG(SS);
+
+  ASSERT_EQ(static_cast<size_t>(UCONTEXT_FPREGS_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.fpregs));
+
+  ASSERT_EQ(static_cast<size_t>(UCONTEXT_FPREGS_MEM_OFFSET),
+            offsetof(ucontext_t,__fpregs_mem));
+#else
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.gregs));
+#endif
+}
+
+TEST(AndroidUContext, SigmakOffset) {
+  ASSERT_EQ(static_cast<size_t>(UCONTEXT_SIGMASK_OFFSET),
+            offsetof(ucontext_t,uc_sigmask));
+}