Adding third_party/openh264/src, build files and unittests

third_party/openh264/buildnotes.txt

Index: third_party/openh264/buildnotes.txt
diff --git a/third_party/openh264/buildnotes.txt b/third_party/openh264/buildnotes.txt
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+# Notes, just me trying to understand the .mk files with pseudocode...
+# Probably the main thing about building asm is making sure the -D defines are
+# set for each platform, and maybe -fPIC, etc compiler options are essential.
+
+# --------- arch.mk ---------
+#  if ARCH == *86 || ARCH == x86_64
+#    x86-common.mk
+#  if ARCH == arm* && ARCH != arm64 && USE_ASM
+#    ASM_ARCH = arm
+#    ASM_FLAGS += codec/common/arm
+#    CFLAGS += -DHAVE_NEON
+#  if ARCH == arm64 || aarch64
+#    ASM_ARCH = arm64
+#    ASMFLAGS += codec/common/arm64
+#    CFLAGS += -DHAVE_NEON_AARCH64
+
+# --------- x86-common.mk ---------
+#  CFLAGS_M32 = -m32
+#  CFLAGS_M64 = -m64
+#  ASM_INCLUDES = codec/common/x86
+#  if ENABLE64BIT
+#    ARCH = x86_64
+#  else
+#    ARCH = x86
+#  if ARCH == x86_64
+#    CFLAGS += -m64
+#    LDFLAGS += -m64
+#    ASMFLAGS_PLATFORM = -DUNIX64
+#  else
+#    CFLAGS += -m32
+#    LDFLAGS += -m32
+#    ASMFLAGS_PLATFORM = -DX86_32
+#  if USE_ASM
+#    CFLAGS += -DX86_ASM
+#    if ARCH != x86_64
+#      CFLAGS += -DX86_32_ASM
+#    ASM_ARCH = x86
+#  ASM = nasm
+#  ASMFLAGS += <ASMFLAGS_PLATFORM>
+
+# --------- platform-linux.mk ---------
+#  include arch.mk
+#
+#  <SHAREDLIBSUFFIX, SHAREDLIBSUFFIXVER, SHLDFLAGS, AR_OPTS set...>
+#
+#  CFLAGS += -Wall -fno-strict-aliasing -fPIC -MMD -MP
+#  if ASM_ARCH == x86
+#    if ARCH == x86_64
+#      ASMFLAGS += -f elf64
+#    else
+#      ASMFLAGS += -f elf
+#  if ASM_ARCH == arm
+#    ASMFLAGS += -march=armv7-a -mfpu=neon
+#
+#  if CXX == clang++
+#    CXXFLAGS += -Wc++11-compat-reserved-user-defined-literal
+
+# --------- platform-bsd.mk ---------
+#  ...
+#  do we care about this? there's platform-darwin.mk as well for mac
+
+# --------- platform-darwin.mk ---------
+#  include arch.mk
+#
+#  <SHAREDLIB_DIR, SHAREDLIBSUFFIX, SHAREDLIBSUFFIXVER, SHLDFLAGS, SHARED set...>
+#
+#  CFLAGS += -Wall -fPIC -MMD -MP
+#  LDFLAGS += -lpthread
+#  if ASM_ARCH == x86
+#    ASMFLAGS += -DPREFIX
+#    if ARCH == x86_64
+#      ASMFLAGS += -f macho64
+#    else
+#      ASMFLAGS += -f macho
+#      LDFLAGS += -read_only_relocs suppress
+
+# --------- platform-ios.mk ---------
+#  ARCH = armv7
+#  include platform-darwin-mk
+#  CXX = clang++
+#  CC clang
+#  if ARCH == *86 || ARCH == x86_64
+#    SDKTYPE = iPhoneSimulator
+#  else
+#    SDKTYPE = iPhoneOS
+#  SDK = <... shell command for sdk version ...>
+#  SDK_MIN = 5.1
+#
+#  <XCODE, SDKROOT set...>
+#
+#  CFLAGS += <...>
+#  LDFLAGS += <...>
+
+# --------- platform-msvc.mk ---------
+# --------- platform-msvc-app.mk ---------
+# --------- platform-msvc-wp.mk ---------
+#  Visual Studio builds (win and win phone), don't care about these?
+#  - Actually Visual Studio is used to build win, not mingw? Care!
+
+# --------- platform-mingw_nt.mk ---------
+#    i.e. Windows when not building with Visual Studio?
+#  include x86-common.mk
+#
+#  <SHAREDLIB_DIR, SHAREDLIBSUFFIX, SHAREDLIBSUFFIXVER, EXTRA_LIBRARY, SHLDFLAGS set...>
+#
+#  CFLAGS += -MMD -MP
+#  LDFLAGS +=  # empty line wtf?
+#  if ARCH == x86_64
+#    ASMFLAGS += -f win64
+#    ASMFLAGS_PLATFORM = -DWIN64
+#    CC = x86_64-w64-mingw32-gcc
+#    CXX = x86_64-w64-mingw32-g++
+#    AR = x86_64-w64-mingw32-ar
+#  else
+#    ASMFLAGS += -f win32 -DPREFIX
+#  EXEEXT = .exe
+
+# --------- platform-android.mk ---------
+#  ARCH = arm
+#  include arch.mk
+#
+#  <SHAREDLIBSUFFIX, SHAREDLIBSUFFIXVER, SHLDFLAGS, NDKLEVEL set...>
+#
+#  if ARCH == arm
+#    if APP_ABI != armeabi
+#      CFLAGS += -march=armv7-a -mfloat-abi=softfp
+#      CFLAGS += -mfpu=vfpv3-d16
+#      LDFLAGS += -march=armv7-a -Wl,--fix-cortex-a8
+#      APP_ABI = armeabi-v7a
+#  else if ARCH == arm64
+#    APP_ABI = arm64_v8a
+#  else if ARCH == x86
+#    if USE_ASM
+#      ASMFLAGS += -f elf64
+#  else
+#    APP_ABI = <ARCH>
+#
+#  ifndef NDKROOT
+#    <ERROR NDKROOT is not set>
+#  ifndef TARGET
+#    <ERROR TARGET is not set>
+#
+#  ...
+