Audio V4: Update namespace and version of 4.0 shim

Put the shim in a V4_0 namespace to comply with the ODR.
Make the include guard unique.
Split from the error prone interface adaptation change for safer review.

Patch generated with:
sed -i 's/V2_0/V4_0/g' *
sed -i "/include.*2.0/s/2\.0/4.0/" *
sed -i '/namespace android *{/anamespace V4_0 {' *
sed -Ei 's/(ifndef|define|endif)(.*)_H/\1\2_4_0_H/' *
sed -Ei 's#}(.*)namespace android$#}\1namespace V4_0\n\0#' *

Bug: 38184704
Test: Compile
Change-Id: I7d3aa46b3dfec664cbeea8a6b946456b8e8f06e3
Merged-In: I7d3aa46b3dfec664cbeea8a6b946456b8e8f06e3
Cherry-picked from master
Signed-off-by: Kevin Rocard <krocard@google.com>
diff --git a/media/libaudiohal/4.0/DeviceHalLocal.cpp b/media/libaudiohal/4.0/DeviceHalLocal.cpp
index fc098f5..e64eee1 100644
--- a/media/libaudiohal/4.0/DeviceHalLocal.cpp
+++ b/media/libaudiohal/4.0/DeviceHalLocal.cpp
@@ -23,6 +23,7 @@
 #include "StreamHalLocal.h"
 
 namespace android {
+namespace V4_0 {
 
 DeviceHalLocal::DeviceHalLocal(audio_hw_device_t *dev)
         : mDev(dev) {
@@ -196,4 +197,5 @@
     mDev->close_input_stream(mDev, stream_in);
 }
 
+} // namespace V4_0
 } // namespace android