[build] enforce specific version of clang format

And ajust .clang-format options to work with the version we fetch.

Change-Id: I58c6d99160eb7820652c68d5d86d864e75f45e3d

.clang-format

@@ -2,6 +2,9 @@ Language: Cpp
 ColumnLimit: 0
 UseTab: Never
 IndentWidth: 4
+IndentCaseLabels: false
+AlignAfterOpenBracket: Align
+SpacesBeforeTrailingComments: 1
 BreakBeforeBraces: Attach
 AccessModifierOffset: -4
 DerivePointerAlignment: false

scripts/clang-fmt

@@ -14,14 +14,10 @@ fi
 # There might be more than one clang-format tool, specially if chromium's
 # depot tools are in the path. Try to use the system one.
 
-CLANGFMT=/usr/bin/clang-format
+CLANGFMT=./clang-format
 
 if [ ! -f $CLANGFMT ]; then
-  # try local dir
-  CLANGFMT=./clang-format
-fi
-if [ ! -f $CLANGFMT ]; then
-  echo "$CLANGFMT not found. Go to http://llvm.org/releases/ to get it."
+  echo "$CLANGFMT not found. Run scripts/fetch-clang-fmt to get it."
   exit 0
 fi