Add /proc/cpuinfo to RuntimeInfo.

Test: adb shell vintf
Bug: 37513906
Change-Id: I94617cb2ca0ae961ec56b2d22b663ecafbcbed48
diff --git a/RuntimeInfo-target.cpp b/RuntimeInfo-target.cpp
index 3b094c9..8f3d8b4 100644
--- a/RuntimeInfo-target.cpp
+++ b/RuntimeInfo-target.cpp
@@ -28,6 +28,10 @@
 #include <sys/utsname.h>
 #include <unistd.h>
 
+#include <fstream>
+#include <iostream>
+#include <sstream>
+
 #include <cutils/properties.h>
 #include <selinux/selinux.h>
 #include <zlib.h>
@@ -135,6 +139,14 @@
 
 status_t RuntimeInfoFetcher::fetchCpuInfo() {
     // TODO implement this; 32-bit and 64-bit has different format.
+    std::ifstream in{"/proc/cpuinfo"};
+    if (!in.is_open()) {
+        LOG(WARNING) << "Cannot read /proc/cpuinfo";
+        return UNKNOWN_ERROR;
+    }
+    std::stringstream sstream;
+    sstream << in.rdbuf();
+    mRuntimeInfo->mCpuInfo = sstream.str();
     return OK;
 }