1. Fix memory leaks reported by running a simple test using ASAN

runtime/vm/cpuinfo_linux.cc

Index: runtime/vm/cpuinfo_linux.cc
diff --git a/runtime/vm/cpuinfo_linux.cc b/runtime/vm/cpuinfo_linux.cc
index e58bac1fe6a0d5f2f6bb953a6904038386854b8b..8d76233194a59cb0ef9416dcb362f79ffb886af6 100644
--- a/runtime/vm/cpuinfo_linux.cc
+++ b/runtime/vm/cpuinfo_linux.cc
@@ -67,7 +67,10 @@ void CpuInfo::Cleanup() {
 
 bool CpuInfo::FieldContains(CpuInfoIndices idx, const char* search_string) {
   if (method_ == kCpuInfoCpuId) {
-    return strstr(CpuId::field(idx), search_string);
+    const char* field = CpuId::field(idx);
+    bool contains = (strstr(field, search_string) != NULL);
+    free(const_cast<char*>(field));
+    return contains;
   } else {
     ASSERT(method_ == kCpuInfoSystem);
     return ProcCpuInfo::FieldContains(FieldName(idx), search_string);
@@ -75,23 +78,6 @@ bool CpuInfo::FieldContains(CpuInfoIndices idx, const char* search_string) {
 }
 
 
-bool CpuInfo::FieldContainsByString(const char* field,
-                                    const char* search_string) {
-  if (method_ == kCpuInfoCpuId) {
-    for (int i = 0; i < kCpuInfoMax; i++) {
-      if (strcmp(field, fields_[i]) == 0) {
-        return FieldContains(static_cast<CpuInfoIndices>(i), search_string);
-      }
-    }
-    UNIMPLEMENTED();
-    return false;
-  } else {
-    ASSERT(method_ == kCpuInfoSystem);
-    return ProcCpuInfo::FieldContains(field, search_string);
-  }
-}
-
-
 const char* CpuInfo::ExtractField(CpuInfoIndices idx) {
   if (method_ == kCpuInfoCpuId) {
     return CpuId::field(idx);
@@ -102,22 +88,6 @@ const char* CpuInfo::ExtractField(CpuInfoIndices idx) {
 }
 
 
-const char* CpuInfo::ExtractFieldByString(const char* field) {
-  if (method_ == kCpuInfoCpuId) {
-    for (int i = 0; i < kCpuInfoMax; i++) {
-      if (strcmp(field, fields_[i]) == 0) {
-        return ExtractField(static_cast<CpuInfoIndices>(i));
-      }
-    }
-    UNIMPLEMENTED();
-    return NULL;
-  } else {
-    ASSERT(method_ == kCpuInfoSystem);
-    return ProcCpuInfo::ExtractField(field);
-  }
-}
-
-
 bool CpuInfo::HasField(const char* field) {
   if (method_ == kCpuInfoCpuId) {
     return (strcmp(field, fields_[kCpuInfoProcessor]) == 0) ||