Fixing install-build-deps.sh to install the correct version of libstdc++ with debugging symbols.

build/install-build-deps.sh

Index: build/install-build-deps.sh
diff --git a/build/install-build-deps.sh b/build/install-build-deps.sh
index 43b5545398ea2bb3123ad70b857af30e1c0deb39..b493ccaed718e970a4b851066afd116544cd62ed 100755
--- a/build/install-build-deps.sh
+++ b/build/install-build-deps.sh
@@ -137,8 +137,16 @@ dbg_list="libatk1.0-dbg libc6-dbg libcairo2-dbg libfontconfig1-dbg
           libpixman-1-0-dbg libsqlite3-0-dbg libx11-6-dbg libxau6-dbg
           libxcb1-dbg libxcomposite1-dbg libxcursor1-dbg libxdamage1-dbg
           libxdmcp6-dbg libxext6-dbg libxfixes3-dbg libxi6-dbg libxinerama1-dbg
-          libxrandr2-dbg libxrender1-dbg libxtst6-dbg zlib1g-dbg
-          libstdc++6-4.6-dbg"
+          libxrandr2-dbg libxrender1-dbg libxtst6-dbg zlib1g-dbg"
+
+# Find the proper version of libstdc++6-4.x-dbg.

[Lei Zhang, 2015/03/16 20:45:42]

I think the logic should be:
precise -> 4.6
trusty -> 4.8
else 4.9

Where we assume "else" means newer than trusty. Everything between precise and
trusty has reached EOL and shouldn't be supported. I'll make a pass after this
CL to clean up the script.

[lfg, 2015/03/16 20:58:47]

Done.

+if [ "x$lsb_release" == "xtrusty" ]; then

[Lei Zhang, 2015/03/16 20:45:42]

A single '=' will do, '==' is a bashism.

[lfg, 2015/03/16 20:58:47]

Done.

+  dbg_list="${dbg_list} libstdc++6-4.8-dbg"
+elif [ "x$lsb_release" == "xutopic" ]; then
+  dbg_list="${dbg_list} libstdc++6-4.9-dbg"
+else
+  dbg_list="${dbg_list} libstdc++6-4.6-dbg"
+fi
 
 # 32-bit libraries needed e.g. to compile V8 snapshot for Android or armhf
 lib32_list="linux-libc-dev:i386"