Track GVR version for each headset type using UMA.

- A data point is only collected at most once between Chrome restarts.
- The data point is either collected once the user navigates to a page that uses WebVR API or enters VrShell.
- The GVR version is retrieved from Java and uploaded in native. By doing so, we can also track if older, non-supported versions of GVR were installed at the time the user tried to use a VR feature.
- The GVR version is encoded as (major * 10^6 + minor * 10^3 + patch) and reported as a UMA_HISTOGRAM_SPARSE_SLOWLY for the headset types CARDBOARD, DAYDREAM and UNKNOWN.

BUG=706436

Review-Url: https://codereview.chromium.org/2865463003
Cr-Commit-Position: refs/heads/master@{#476705}

• chrome/android/BUILD.gn[diff]
• chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrCoreInfo.java[Added - diff]
• chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrCoreVersionChecker.java[diff]
• chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrCoreVersionCheckerImpl.java[diff]
• chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java[diff]
• chrome/android/java_sources.gni[diff]
• chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/MockVrCoreVersionCheckerImpl.java[diff]
• chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/WebVrTest.java[diff]
• chrome/browser/android/chrome_jni_registrar.cc[diff]
• chrome/browser/android/vr_shell/BUILD.gn[diff]
• chrome/browser/android/vr_shell/vr_core_info.cc[Added - diff]
• chrome/browser/android/vr_shell/vr_core_info.h[Added - diff]
• chrome/browser/android/vr_shell/vr_metrics_util.cc[Added - diff]
• chrome/browser/android/vr_shell/vr_metrics_util.h[Added - diff]
• chrome/browser/android/vr_shell/vr_shell_delegate.cc[diff]
• chrome/browser/android/vr_shell/vr_shell_delegate.h[diff]
• chrome/browser/android/vr_shell/vr_shell_gl.cc[diff]
• tools/metrics/histograms/histograms.xml[diff]